,,univ]sity ,,( ,,kansas ,,publications 
,,museum ,,( ,,natural ,,hi/ory  ,volume
 #ab1 ,no4 #aj1 pp4 #dge-eja1 #g figs4  
,octob] #be1 #aifc  ,a ,new ,g5us (     
,p5nsylvanian ,fi% 7,crossopt]ygii1     
,coelacan?i=mes7 f ,kansas  ,,by  ,,joan
 ,,e*ols  ,,univ]sity ,,( ,,kansas      
,,lawr5ce #aifc   ,,univ]sity ,,(       
,,kansas ,,publications1 ,,museum ,,(   
,,natural ,,hi/ory  ,editors3 ,e4       
,raymond ,hall1 ,*airman1 ,h5ry ,s4     
,fit*1 ,!odore ,h4 ,eaton1 ,jr4         
,volume #ab1 ,no4 #aj1 pp4 #dge-eja1 #g 
figs4 ,publi%$ ,octob] #be1 #aifc       
,,univ]sity ,,( ,,kansas ,lawr5ce1      
,kansas  ,,pr9t$ ,,by ,,jean ,m4        
,,neib>g]1 ,,/ate ,,pr9t] ,,topeka1     
,,kansas #aifc  ,transcrib]'s ,note3    
,words surr\nd$ by tildes1 l ?is        
signifies words 9 bold4 ,words surr\nd$ 
by und]scores1 l ?is1 signifies words 9 
italics4     ,a ,new ,g5us (            
,p5nsylvanian ,fi% 7,crossopt]ygii1     
,coelacan?i=mes7 f ,kansas  ,,by  ,,joan
 ,,e*ols   ,,introduction  ,9 #aica &   

#aicb1 ,h4 ,h4 ,lane1 ,c4 ,w4 ,hibb>d & 
,w4 ,k4 ,mc,nown collect$ ! specim5s t  
,hibb>d 7#aicc7 describ$ & made ! basis 
( two new species4 ,^! 7 f ! ,rock ,lake
 %ale memb] ( ! ,/anton =mation1 six    
miles nor?we/ ( ,g>nett1 ,&]son ,c\nty1 
,kansas4 ,9 #aied1 f a locality         
7,k,an-#a_/;,d1 see page #dhj7          
approximately "o f\r? mile s\?we/ ( !   
fir/ locality1 specim5s 7 qu>ri$ by ,f4 
,e4 ,peabody1 ,r4 ,w4 ,wilson & ,r4     
,weeks4 ,9 #aiee ,r4 ,r4 ,camp collect$ 
additional blocks ( ,rock ,lake %ale f  
?is second locality4 ,/udy ( all ( !    
mat]ials f ! above m5tion$ localities   
reveals ! exi/5ce ( an hi!rto           
unrecogniz$ g5us ( coelacan?4 ,x is nam$
 & describ$ bel[4  ,i wi% to ?ank ,pr(4 
,!odore ,h4 ,eaton1 ,jr41 = sugge/+ !   
project & = mu* helpful advice4 ,i am   
indebt$ to ,dr4 ,e4 ,i4 ,:ite ( !       
,briti% ,museum 7,natural ,hi/ory7 =    
furni%+ a ca/ ( ! endocranium (         
,rhabdod]ma elegans 7,newb]ry7 =        
comp>ison1 & to ,drs4 ,donald ,baird    

7,pr9ceton ,univ]sity71 ,bobb ,s*aeff]  
7,am]ican ,museum ( ,natural ,hi/ory7 & 
,r4 ,h4 ,d5ison 7,*icago ,natural       
,hi/ory ,museum7 = loans & ex*anges (   
specim5s = comp>ison4 ,i am grateful to 
,dr4 ,bobb ,s*aeff] = advice on !       
manuscript4 ,mr4 ,m]ton ,c4 ,b[man      
assi/$ ) ! illu/rations4 ,! /udy "h     
report$ on 0 made :ile ,i 0 a ,rese>*   
,assi/ant support$ by ,national ,sci5ce 
,f\ndation ,grant ,g-#adjac4            
,,sy/ematic ,,descriptions  ,subclass   
,,crossopt]ygii  ,sup]ord] ,,coelacan?i 
,ord] ,coelacan?i=mes  ,subord]         
,,diploc]cidoidei  ,family              
,,diploc]cidae  ,subfamily              
,rhabdod]mat9ae1 new subfamily          
,type g5us4--,rhabdod]ma ,reis1 #ahhh1  
,paleontographica1      vol4 #ce1 p4    
#ga4       ,ref]r$ g5us4--,synaptotylus 
new1 describ$ bel[4                     
,horizon4--,c>bonif]\s4                 
,diagnosis4--,sph5e?moid region p>tly   
ossifi$1 &      consi/+ ( basisph5oid1  
p>asph5oid1 & e?moid      ossifications2

 pair$ basipt]ygoid process & pair$     
antotic process on basisph5oid2         
p>asph5oid ( normal      size1 & closely
 associat$ )1 or fus$ to1               
basisph5oid2 e?moids pair$ 9 ,rhabdod]ma
 7unkn[n 9      ,synaptotylus74         
,discussion4--,because ( ! great        
diff]5ces 9 endocranial /ructure betwe5 
! ,devonian & ,p5nsylvanian coelacan?s1 
!y are "h plac$ 9 new subfamilies4 ,!   
two propos$ subfamilies ( ! family      
,diploc]cidae are ! ,diploc]c9ae & !    
,rhabdod]mat9ae4 ,! ,diploc]c9ae include
 ^? coelacan?s hav+ two l>ge unpair$    
bones 9 ! endocranium 7at pres5t ?is    
includes ,diploc]cides ,/5sioe1 ,nesides
 ,/5sioe & ,euporo/eus ,jaekel74 ,!     
subfamily ,rhabdod]mat9ae is compos$ (  
coelacan?s hav+ r$uc$ endocranial       
ossification1 z describ$ 9 detail above1
 & n[ includ+ ,rhabdod]ma ,reis &       
,synaptotylus n4 g4  ,memb]s ( ?is      
subfamily diff] f ^? ( ! subfamily      
,diploc]c9ae 9 hav+ sev]al pair$ &      
unpair$ elem5ts 9 ! sph5e?moid region ( 

! endocranium1 in/ead ( only "o l>g]    
ossification4 ,!y diff] f ^? ( ! subord]
 ,coelacan?oidei 9 ! ret5tion (         
basipt]ygoid processes4  ,synaptotylus  
is m closely relat$ to ,rhabdod]ma ?an  
to ! ,diploc]c9es because ! ant]ior     
portion ( ! endocranium conta9s only a  
basisph5oid1 p>asph5oid1 & probably     
e?moids4 ,! sph5e?moid region 0 c]ta9ly 
n a l>ge1 unpair$ unit z 9 !            
,diploc]c9es4 ,probably ! po/]ior "p1 ! 
otico-occipital region 7n kn[n 9        
,synaptotylus71 0 mu* m ne>ly l t (     
,rhabdod]ma1 :i* consi/$ ( unpair$      
basioccipital & supraoccipital1 & pair$ 
prootics1 exoccipitals1 & ant]ior &     
po/]ior occipital ossifications         
7,moy-,?omas1 #aicg3 figs4 #c1 #d74     
,moy-,?omas 7#aicg3chi7 po9ts out t 9   
,rhabdod]ma ! occipital region is       
consid]ably m ossifi$ ?an 9 any         
coelacan?s o!r ?an ! ,devonian =ms4 ,b]g
 7#aidj3cij7 ?\ght t ! ,c>bonif]\s      
coelacan?s %\ld be plac$ 9 a sep>ate    
family because !y did n h two l>ge1     

unpair$ bones 9 ! endocranium4          
,rhabdod]ma & ,synaptotylus repres5t    
ano!r /age 9 evolution ( ! endocranium 9
 coelacan?s1 &1 if classification is to 
be bas$ on endocranial /ructure1 !n ?is 
/age 7repres5t$ by ! two g5]a7 may lat] 
be giv5 family rank z ,b]g sugge/$4     
,because ,rhabdod]ma & ,synaptotylus h  
only "p ( ! sph5e?moid region ossifi$ & 
because !y reta9 basipt]ygoid processes1
 !y are consid]$ to be relat$ & are     
includ$ 9 ! subfamily ,rhabdod]mat9ae4  
,synaptotylus1 new g5us       ,type     
species4--,synaptotylus newelli         
7,hibb>d74       ,horizon4--,rock ,lake 
%ale memb]1 ,/anton =mation1      ,lans+
 gr\p1 ,miss\ri s]ies1 ,upp]            
,p5nsylvanian4  ,diagnosis4--,late      
,p5nsylvanian fi%es ( small size1 hav+ !
 foll[+ comb9ation ( *>act]s3 on        
basisph5oid1 knoblike antotic processes 
connect$ by a l[ ridge to basipt]ygoid  
processes2 entire v5tral surface (      
p>asph5oid too!d2 ant]ior m>g9 (        
p>asph5oid not*$ & no evid5ce (         

hypophyseal op5+4 ,d]mal bones ( skull  
smoo? or ) l[1 r\nd$ tub]cles & /riae2  
fronto-e?moid %ield incompletely kn[n b 
hav+ "o pair ( l>ge rectangul> frontals 
) po/]olat]ally slant+ ant]ior m>g9s2   
int]temporals l>ge1 ! lat]al m>g9s curv+
 lat]ally2 po/orbital triangul>1 apex   
d[nw>d2 subop]cul> some:at triangul>2   
squamosal c>ry+ s5sory canal t curves   
d[n po/]iorly & ext5ds onto a v5tral    
projection2 op]cul> g5]ally triangul>2  
supratemporals elongate1 curv+ to fit   
lat]al m>g9 ( int]temporals2            
circumorbital plates lightly ossifi$4   
,palatoquadrate complex consi/+ (       
endopt]ygoid & ectopt]ygoid 7bo? too!d  
on m$ial surface71 quadrate1 &          
metapt]ygoid1 ! latt] smoo? & hav+ wid5$
 bord] = articulation on ant]odorsal    
m>g94 ,pectoral girdle consi/+ (        
clei?rum & clavicle 7supraclei?rum n    
se572 small projection on m$ial surface 
( po/]ior portion ( clei?rum2 horizontal
 m$ial process on clavicle4 ,pelvic     
plate be>+ ?ree ant]iorly div]g+        

apophyses1 & "o d5ticulate v5trom$ian   
process = articulation to opposite      
plate4 ,lepidotri*ia jo9t$ di/ally1 b n 
tub]culat$4 ,scales oval1 hav+ po/]iorly
 conv]g+ ridges on po/]ior expos$ p>ts4 
,! "n ref]s to ! mo/ di/9ctive "* ( !   
g5us1 ! connect$ antotic & basipt]ygoid 
processes on ! basisph5oid1 & is d]iv$ f
 ,greek1 synaptos--jo9$1 tylos          
7masc47--knob1 projection4              
,synaptotylus is exclud$ f ! advanc$    
subord] ,coelacan?oidei by ! ret5tion ( 
basipt]ygoid processes on ! basisph5oid4
 ,synaptotylus diff]s f ,rhabdod]ma 9   
sev]al *>act]s ( ! basisph5oid1 ! mo/   
important be+3 knoblike antotic         
processes 7^? ( ,rhabdod]ma are wid]1 m 
flatt5$ & m dorsal 9 position72 small1  
lat]al basipt]ygoid processes 79        
,rhabdod]ma ^! are l>g] & f>!r v5tral 9 
position74   ,synaptotylus newelli      
7,hibb>d7       ,coelacan?us newelli    
,hibb>d1 #aicc1 ,univ4 ,kansas ,sci4    
,bull41 #ba3bhj1 pl4 #bg1 figs4 #b1 #c4 
,coelacan?us arcuatus ,hibb>d1 #aicc1   

,univ4 ,kansas ,sci4      ,bull41       
#ba3bhb1 pl4 #bf1 fig4 #h2 pl4 #bg1 fig4
 #a4       ,rhabdod]ma elegans          
,moy-,?omas1 #aicg 79 "p71 ,proc4       
,zool4 ,soc4 ,london1 #ajg7s]4 ,b1 pt4  
#c73cii4       ,type4--,k4 ,u4 no4      
#ghf;,f4       ,diagnosis4--,same z = ! 
g5us4       ,horizon4--,rock ,lake %ale 
memb]1 ,/anton =mation1      ,lans+     
gr\p1 ,miss\ri s]ies1 ,upp]             
,p5nsylvanian4       ,localities4--,!   
specim5s /udi$ by ,hibb>d 7,k4 ,u4 nos4 
#ghf;,f1 #ghg;,f1 #ghh7 & no4 #aadeg 7  
tak5 f ! ,brad=d      ,*&l] f>m1 f !    
orig9al qu>ry 9 ,,sw-#a_/d1 ,,se-#a_/d1 
sec4 #cb1 ,t4#ai,s1 ,r4#ai;,e4 ,!       
rema9d] 7 collect$ f      ,univ]sity (  
,kansas ,museum ( ,natural ,hi/ory      
locality      ,k,an-#a_/;,d1 a qu>ry 9  
sec4 #e1 ,t4#ai,s1 ,r4#ai;,e4 ,bo? ( ^! 
are      approximately six miles nor?we/
 ( ,g>nett1 ,&]son      ,c\nty1 ,kansas4
       ,ref]r$ specim5s4--,k4 ,u4 nos4  
#ghf;,f1 #ghg;,f1 #ghh1 #iici1          
#aadbd1 #aadbe1 #aadbf1 #aadbg1 #aadbh1 

#aadbi1 #aadcj1 #aadca1      #aadcb1    
#aadcc1 #aadcd1 #aaddi1 #aadej1 #aadea1 
#aadeb1 #aadec1      #aaded1 #aadee1    
#aadeg4                                 
,pres]vation4--,pres]vation ( _m ( !    
specim5s is      good1 few are wea!r$1 b
 mo/ ( ! rema9s are      fragm5t>y &    
dissociat$4 ,"o specim5 7! type1 no4    
#ghf;,f7 & half ( ano!r 7 ne>ly         
complete4 ,specim5s      are f\nd       
scatt]$ ?r\gh\t ! ,rock ,lake %ale 7see 
p4      #dih74                          
,morphology4--,t]m9ology us$ = bones ( !
 skull is      t ( ,moy-,?omas 7#aicg7 &
 ,s*aeff] 7#aieb74   ,endocranium &     
p>asph5oid  ,illu/ration3 ,,fig4 #a4    
,synaptotylus newelli 7,hibb>d74        
,re/oration ( ! basisph5oid1 bas$ on ,k4
 ,u4 no4 #iici1 x #e4 ,a1 lat]al view1  
,b1 po/]ior view1 ,c1 v5tral view4  ,!  
basisph5oid 7see fig4 #a7 has be5 obs]v$
 9 only "o specim5 7,k4 ,u4 no4 #iici7 9
 po/]odorsal & v5tral views4 ,!         
basisph5oid1 al?\gh some:at cru%$1      
appe>s to be fus$ to ! p>asph5oid4 ,bo? 

antotic & basipt]ygoid processes are    
pres5t1 & are connect$ by a l[1 r\nd$   
ridge4 ,! antotic processes are l>ge1   
bulb> projections4 ,^! processes 9      
,rhabdod]ma are wid] & m flatt5$        
7,moy-,?omas1 #aicg3;figs4 #c1 #d74 ,!  
antotic processes are at mid-po9t on !  
lat]al surface1 n dorsal z 9            
,rhabdod]ma1 & bo? ! processes & ! ridge
 are direct$ ant]ov5trally4 ,!          
basipt]ygoid processes are small]1      
some:at v]tically elongat$ projections1 
situat$ at ! end ( ! l[ connect+ ridge  
ext5d+ ant]ov5trally f ! antotic        
processes1 & are n basal z are ^? (     
,rhabdod]ma4 ,! sph5oid condyles1 se5 9 
po/]ior view1 issue f ! dorsal m>g9 ( ! 
noto*ordal socket4 ,! m>g9s ( ! socket  
are r\nd$1 & slope d[n ev5ly to ! c5t]4 
,a slight depression situat$ betwe5 &   
dorsal to ! sph5oid condyles is         
suppos$ly = ! atta*m5t ( ! int]cranial  
ligam5t 7,s*aeff] & ,gregory1           
#aifa3;fig4 #a74 ,! alisph5oids ext5d   
upw>d1 ant]odorsally f ! region above ! 

sph5oid condyles1 & may connect to      
ridges on ! v5tral surface ( ! frontals4
 ,! lat]al lam9ae are n pres]v$1 & _!   
ext5t is unkn[n4  ,9 view+ ! *anges 9 ! 
endocranium ( ,c>bonif]\s & ,p]mian     
coelacan?s1 x w\ld be well to consid] ! 
me*anical relation%ip ( ! loss ( !      
basipt]ygoid processes to ! effect on   
swall[+ prey4 ,evid5tly _m ( !          
coelacan?s1 ,latim]ia = example1 are    
pr$ators 7,smi?1 #aici3ajd72 to su*     
fi%es a m effici5t cat*+ & swall[+      
me*anism w\ld be an adaptive improvem5t4
 ,/5sioe 7#aicb3;fig4 #ad7 pres5ts a    
cross section ( ! e?mosph5oid moiety ( !
 endocranium ( ,diploc]cides kays]i 7von
 ,ko557 %[+ ! metapt]ygoid ( !          
palatoquadrate loosely articulat$ to bo?
 ! antotic & basipt]ygoid processes4    
,accord+ to ,t*]nav9 7#aidh3acg7 &      
,s*aeff] & ,ros5 7#aifa3aij7 ! swall[+ (
 l>ge prey dep5ds on ! ability ( ! fi%  
to exp& its oral cavity by all[+ !      
po/]ov5tral portion ( ! palatoquadrate &
 ! po/]ior end ( ! m&ible to sw+ outw>d4

 ,:]e ! palatoquadrate articulates ) !  
basisph5oid at ! antotic & basipt]ygoid 
processes1 z 9 ! ,devonian coelacan?s1 x
 c n sw+ s f> lat]ally z :]e x          
articulates ) only ! dorsal1 antotic    
process4 ,p]haps ! loss ( ! basipt]ygoid
 articulation reflects ! developm5t ( a 
m effici5t me*anism = swall[+ prey 9 ^! 
fi%es4 ,s*aeff] & ,ros5 7#aifa3aia1     
#aic7 %[ t 9 ! evolution ( !            
act9opt]ygians sev]al *anges improv$ !  
fe$+ me*anism3 "s ( ^! *anges are3 7#a7 
free+ ( ! maxilla f ! *eek1 giv+ a l>g] 
*amb] = ! action ( ! adductor m&ibulae2 
7#b7 developm5t ( a coronoid process on 
! m&ible2 & 7#c7 increase 9 torque ar\nd
 ! jaw articulation4 ,9 coelacan?s1 at  
lea/ "s comp>able *anges occurr$1 su* z3
 7#a7 loss ( ! maxill>y1 ?us increas+ ! 
size ( ! adductor *amb]2 7#b7 developm5t
 ( ! coronoid bone1 af=d+ a great] area 
= muscle atta*m5t2 7#c7 developm5t ( an 
ar*$ dorsal m>g9 on ! angul>2 7#d7      
modification ( ! palatoquadrate complex1
 ) resultant loss ( ! basipt]ygoid      

processes4 ,9 ,synaptotylus !           
basipt]ygoid processes are small1 n     
basally locat$1 & p]haps n functional4  
,a m effici5t fe$+ me*anism develop$    
rapidly dur+ ! ,c>bonif]\s & has rema9$ 
almo/ unalt]$4  ,illu/ration3 ,,fig4 #b4
 ,synaptotylus newelli 7,hibb>d74       
,re/oration ( ! p>asph5oid1 bas$ on ,k4 
,u4 nos4 #iici1 #aadea1 x #e4 ,a1 v5tral
 view1 ,b1 dorsal view & cross sections4
  ,! p>asph5oid 7see fig4 #b7 is a      
%ovel-%ap$ bone hav+ a wide ant]ior     
portion & a n>r[] po/]ior portion (     
ne>ly uni=m wid?4 ,mo/ ( ! v5tral       
surface is cov]$ ) m9ute granul> tee?4  
,! ant]ior m>g9 is fl>$ & curv$         
po/]om$ially f ! lat]al m>g9 to a m$ian 
triangul> projection4 ,! lat]al m>g9s   
curve smoo?ly f ! greate/ ant]ior wid?  
to ! n>r[ c5tral portion1 :]e ! m>g9s   
become some:at ?ick5$ & turn$ dorsally4 
,po/]ior to ?is ! lat]al m>g9s are      
probably ne>ly /raight4 ,! ext]nal      
surface ( ! ant]ior section is ne>ly    
flat & has a c5tral depress$ area !     

sides ( :i* slope ev5ly to ! c5t]4 ,!   
int]nal surface is smoo? & c5trally     
convex4 ,because ( ! fragm5t>y nature ( 
all f\r obs]v$ specim5s1 total l5g? 0 n 
measur$ b is e/imat$ to be #ae to #bj   
mm4 ,! op5+ ( ! hypophyseal canal 0 n   
pres5t1 possibly because ( cru%+4       
,e?moidal ossifications 7 n pres]v$ 9   
any ( ! specim5s /udi$4 ,! p>asph5oid   
diff]s f t ( ,rhabdod]ma elegans        
7,newb]ry7 9 be+ m fl>$ & wid5$         
ant]iorly & m concave c5trally4   ,d]mal
 bones ( ! skull  ,v>i\s portions ( !   
cranial ro( are pres]v$ 9 sev]al        
specim5s 7see fig4 #c74 ,= comp>isons ) 
,rhabdod]ma elegans1 see ,moy-,?omas    
7#aicg3;fig4 #a74  ,! premaxill>ies &   
ro/ral elem5ts are n pres]v$ 9 any ( !  
specim5s4 ,only "o pair ( relatively    
l>ge frontals h be5 obs]v$2 !y are #e4e 
to #i4j mm4 long & #b4j to #c4e mm4     
wide4 ,^! are ne>ly flat bones1 ) !     
greate/ wid? po/]iorly #j4a to #a4j mm4 
wid] ?an ! ant]ior portion4 ,! midl9e   
suture is /raight1 ! lat]al m>g9s are   

ne>ly /raight1 ! ant]ior m>g9 slopes    
ev5ly po/]olat]ally1 & ! po/]ior m>g9 is
 slightly convex to /raight4 ,! ant]ior 
m>g9 9 ,r4 elegans is ess5tially        
/raight4 ,ornam5tation consi/s ( sp>se1 
unev5ly spac$1 co>se tub]cles or %ort   
/riae4 ,9 "o specim5 bo? bones h small  
clu/]s ( tub]cles ne> ! lat]al m>g9s &  
ab\t #b4j mm4 f ! po/]ior m>g94 ,none ( 
^! bones has alisph5oids or ridges on ! 
v5tral surface1 z ,/5sioe 7#aiba3fe1    
#ig7 describ$ = ,wimania & ,axelia4     
,illu/ration3 ,,fig4 #c4 ,synaptotylus  
newelli 7,hibb>d74 ,diagram ( ! d]mal   
bones ( ! skull1 9 lat]al view1 bas$ on 
,k4 ,u4 nos4 #ghh & #aadcb4 x #b-a_/b   
approximately4  ,only six supraorbitals 
h be5 pres]v$ 7see fig4 #c74 ,^! are    
ne>ly squ>e1 flat1 ?9 bones ly+ ne>ly 9 
place adjac5t to a frontal on ,k4 ,u4   
no4 #ghh4 ,! smalle/ is ant]ior2 ! m>g9s
 ( all are ne>ly /raight4 ,! bones are  
unornam5t$4 ,ea* be>s a pore ( !        
supraorbital l9e j bel[ ! midl9e4 ,!    
supraorbitals ( ,r4 elegans h a         

triangul> outl9e & d n be> pores4       
,int]temporals 7fig4 #c7 on sev]al      
specim5s v>y f approximately #i4j to    
#ae4j mm4 9 l5g?1 #b4j to #b4g mm4 9    
ant]ior wid?1 & increase to #d4e to #h4j
 mm4 9 maximum po/]ior wid?4 ,! midl9e  
suture is /raight1 ! ant]ior m>g9 is    
concave & ! lat]al m>g9 proce$s lat]ally
 9 a concave curve to ! wide/ portion4  
,9 ,r4 elegans only ! ant]ior half ( !  
correspond+ m>g9 is concave4 ,! po/]ior 
m>g9 is slightly r\nd$ & slopes         
ant]iorly t[>d ! lat]al m>g94           
,ornam5tation is usually ( r&omly ori5t$
 tub]cles & /riae1 al?\gh /riae are m   
common 9 ! po/]ior ?ird & may be        
longitud9al1 :]eas tub]cles occur ma9ly 
on ! ant]ior section4 ,no evid5ce (     
s5sory pores1 z se5 on ! int]temporal ( 
,r4 elegans1 has be5 f\nd4  ,!          
supratemporals 7 obs]v$ on only "o      
specim5 7,k4 ,u4 no4 #ghh71 7fig4 #c74  
,sutures 7 difficult to di/+ui% b !     
m$ial m>g9 is presum$ to curve to fit & 
to articulate ) ! lat]al m>g9s ( !      

int]temporals4 ,lat]al m>g9s are smoo?ly
 curv$ b ! ant]ior & po/]ior m>g9s 7    
brok5 (f4 ,!re appe>s to be no          
ornam5tation on ?is bone4 ,!            
supratemporals are mu* m elongat$ &     
curv+ ?an ^? 9 ,r4 elegans4  ,! *eek    
region is ne>ly complete 9 "o specim5   
7,k4 ,u4 no4 #ghh71 & scatt]$ p>ts occur
 9 a few o!rs 7see fig4 #c74 ,!         
lacrimojugal ( no4 #ghh is elongate1 )  
bo? ends curv+ dorsally4 ,x diff]s f !  
lacrimojugal 9 ,r4 elegans1 9 :i* !     
ant]ior end ext5ds ant]iorly & is n     
curv$ dorsally4 ,! po/]ior & ant]ior    
m>g9s are n pres]v$2 ! greate/ height   
appe>s to be po/]ior4 ,pores ( !        
suborbital portion ( ! infraorbital     
s5sory canal are se5 on ! dorsal surface
 ( ! bone4 ,9 ,r4 elegans ! pores are on
 ! lat]al surface4 ,a section ( !       
lacrimojugal on specim5 no4 #aadbe1     
brok5 at bo? ends1 %[s a ?9 lay] ( bone 
p]=at$ by ! pores & cov]+ a groove = !  
canal )9 ! dorsal m>g9 ( ! bone4 ,bo?   
specim5s are unornam5t$4  ,a ne>ly      

complete po/orbital 7fig4 #c7 on specim5
 no4 #ghh is ne>ly triangul>1 ) ! apex  
v5tral4 ,! concave ant]ior m>g9 be>s    
pores ( ! po/orbital "p ( ! infraorbital
 l9e4 ,ornam5tation consi/s ( widely    
spac$1 co>se tub]cles4  ,"p ( "o        
squamosal is pres]v$4 ,x is some:at     
triangul> & its apex is v5tral4 ,?is    
bone is associat$ ) ! po/orbital1       
subop]cul> & lacrimojugal on no4 #ghh4  
,! preop]cul> s5sory l9e passes d[n !   
curv+ v5tral m>g9 ( ?is bone1 & ext5ds  
v5trally onto a n>r[ projection4 ,a l[  
ridge1 ne>ly v]tical1 passes dorsally f 
ab\t mid-po9t ( ! canal to ! dorsal     
portion4 ,! ant]ior m>g9 is ne>ly       
/raight1 ! v5tral m>g9 is concave1 & !  
dorsal m>g9 is convex dorsally b may be 
incomplete4 ,p]haps ! squamosal &       
preop]cul> are fus$4 ,! surface appe>s  
smoo?2 ! view may be ( ! m$ial side4 ,! 
squamosal ( ,r4 elegans is ne>ly        
triangul> & notably diff]5t f t (       
,synaptotylus newelli4  ,! subop]cul>   
7fig4 #c7 %[s closely spac$ tub]cles on 

! lat]al surface4 ,! bone is an         
elongat$1 irregul> triangle ) ! apex    
po9t+ ant]odorsally4 ,! m>g9s are       
incomplete1 except = ! concave1 curv+   
ant]ior m>g94  ,num]\s op]cul>s 7fig4   
#c7 occur 9 ! suite ( specim5s1 bo?     
isolat$ & ne>ly 9 place4 ,ea* is        
subtriangul>2 ! apex ( ! triangle is    
v5tral4 ,a slight convexity projects f !
 ant]odorsal bord]4 ,! po/]ior m>g9 is  
broadly b %all[ly ind5t$4 ,o!rwise !    
m>g9s are smoo?4 ,maximum height ranges 
f #h4j to #aa4j mm41 & maximum wid? f   
#h4j to #ac4j mm4 ,ornam5tation v>ies f 
a few widely spac$1 r&omly ori5t$       
tub]cles to closely spac$ tub]cles m]g+ 
po/]iorly into /riae4 ,on "s specim5s ^!
 are p>allel to ! dorsal bord]1 &       
oblique 9 ! c5tral portion4 ,on !       
po/]ior m>g9s ( sev]al op]cul>s ! /riae 
break up into tub]cles4 ,a few op]cul>s 
h closely spac$ tub]cles ov] mu* ( !    
surface4 ,! int]nal surface is smoo?4   
,visc]al skeleton  ,! palatoquadrate    
complex1 be/ se5 on ,k4 ,u4 no4 #iici   

7fig4 #d71 consi/s ( endopt]ygoid1      
ectopt]ygoid1 metapt]ygoid & quadrate4  
,no trace ( epipt]ygoids1 d]mopalat9es  
or autopalat9es1 su* z ,moy-,?omas      
7#aicg3cib1 fig4 #e7 describ$ =         
,rhabdod]ma1 has be5 obs]v$4  ,!        
endopt]ygoid has a long1 v5tral1        
ant]iorly-direct$ process1 & an         
ant]odorsal process t meets !           
metapt]ygoid 9 =m+ ! processus asc5d5s4 
,! suture betwe5 ! endopt]ygoid &       
metapt]ygoid1 se5 9 lat]al view1 is     
di/9ct 9 "s specim5s & has an associat$ 
ridge2 ^! bones appe> to be fus$ 9 o!rs1
 )\t reg>d to size4 ,?is suture curves  
dorsally f a po9t ant]ior to ! quadrate 
& passes ant]odorsally to ! extremity ( 
! processus asc5d5s4 ,! suture is       
visible on ! m$ial side only ne> !      
processus asc5d5s1 = x is cov]$ by a    
dorsal1 too!d ext5sion ( ! endopt]ygoid4
 ,! endopt]ygoid has a smoo? lat]al     
surface2 ! m$ial surface is cov]$ ) t9y 
granul> tee?1 9 *>act]i/ic l9e & dot    
arrangem5t4 ,! tee? ext5d onto ! v5tral 

surface ( ! v5tral process4             
,illu/ration3 ,,fig4 #d4 ,synaptotylus  
newelli 7,hibb>d74 ,re/oration ( !      
palatoquadrate complex1 bas$ on ,k4 ,u4 
no4 #iici1 x #e4 ,a1 m$ial view1 ,b1    
lat]al view4  ,two long1 n>r[1 spl9tlike
 bones cov]$ on "o surface ) granul>    
tee? are int]pret$ z ectopt]ygoids4 ,^! 
are #ac4j & #af4j mm4 long & ea* is #a4e
 mm4 wide4 ,ori5tation ( ^! is unkn[n1 b
 !y probably fitt$ aga9/ ! v5tral       
surface ( ! v5tral process ( !          
endopt]ygoid 7,moy-,?omas1 #aicg3;fig4  
#e74  ,illu/ration3 ,,fig4 #e4          
,synaptotylus newelli 7,hibb>d74 ,a1    
c]atohyal1 lat]al 787 view1 bas$ on ,k4 
,u4 nos4 #aadbi & #aadeg1 x #e4 ,b1     
urohyal1 bas$ on ,k4 ,u4 no4 #aadeg1 x  
#e4  ,! metapt]ygoid has a smoo? surface
 9 bo? views4 ,! dorsal edge has a      
?ick5$1 fl>$ m>g9 t presumably          
articulat$ ) ! antotic process ( !      
basisph5oid4 ,no articul> surface = !   
basipt]ygoid process has be5 obs]v$4  ,!
 quadrate is di/9ct & closely appli$ to 

! po/]ov5tral m>g9 ( ! complex4 ,9 m$ial
 view ! m>g9 is ne>ly /raight & cont9ues
 to ! v5tral edge4 ,! v5tral surface is 
?ick5$ & =ms a r\nd$1 knoblike articul> 
surface4 ,9 lat]al view ! surface is    
smoo?2 ! ant]ior m>g9 is irregul> 7or   
p]haps brok5 on all specim5s71 & proce$s
 9 an irregul> convex curve f ! po/]ior 
to ! v5tral m>g94  ,! g5]al %ape ( !    
palatoquadrate complex is mo/ ne>ly l t 
( ,rhabdod]ma elegans 7,moy-,?omas1     
#aicg3;fig4 #e74 ,! ori5tation ( !      
complex 9 ! liv+ fi% 0 probably oblique1
 ) ! processus asc5d5s ne>ly v]tical1 ! 
quadrate oblique1 & ! v5tral process ( !
 endopt]ygoid ext5d+ dorsoant]iorly &   
articulat+ ) ! p>asph5oid4  ,( ! hyoid  
ar* only ! c]atohyals 7see fig4 #e;,a7  
are pres]v$ 9 sev]al specim5s4 ,^! are  
long1 curv$ bones ) a po/]ov5tral       
process & wid5$1 fl>+ po/]ior m>g94 ,!  
m$ial 787 surface is concave 9 "o       
specim54 ,! lat]al 787 surface displays 
a di/9ct ridge on sev]al specim5s1 aris+
 on ! dorsal surface opposite !         

po/]ov5tral process & ext5d+ diagonally 
to ! ant]ov5tral end ( ! ant]ior limb4  
,! impression ( "o o!r specim5 appe>s to
 h a c5tral ridge because ( great]      
dorsal ?ickness & n>r[ness4 ,bo?        
surfaces are unornam5t$4  ,! urohyal    
7see fig4 #e;,b7 is an unornam5t$1      
,y-%ap$ bone1 ) ! /em ( ! ,y po9t+      
ant]iorly4 ,ori5tation ) respect to     
dorsal & v5tral surfaces is unc]ta94 ,9 
"o view a fa9t ridge1 also ,y-%ap$1     
occurs on ! exp&$ po/]ior portion1 & !  
surface is convex4 ,! ant]ior process   
has a convex surface1 slop+ ev5ly (f to 
! lat]al m>g92 ! opposite side ( !      
process has a concave surface4 ,!       
po/]ior portion has a slightly depress$ 
area 7see fig4 #e;,b7 at ! junction ( ! 
arms ( ! ,y4  ,! five bran*ial ar*es are
 repres5t$ by ! c]atobran*ials1 sev]al (
 :i* are pres]v$ on ,k4 ,u4 no4 #aadca4 
,^! are long bones ) ant]iorly curv+    
v5tral ends4 ,! m$ial surfaces are p>tly
 cov]$ ) m9ute granul> tee?2 only !     
dorsal "p is )\t tee?4 ,! dorsal        

articul> surface is convex dorsally &   
r\nd$4  ,! m&ible 7fig4 #c71 ! be/      
specim5s ( :i* are ,k4 ,u4 nos4 #ghh &  
#aadbe1 is se5 only 9 lat]al & v5tral   
views1 ) only angul>1 spl5ial & d5t>y   
visible4  ,! angul> =ms ! ma9 body ( !  
m&ible1 & is simil> to t ( ,sp]matodus4 
,! dorsal m>g9 ( ! angul> is exp&$ 9 !  
c5tral region1 ) "s v>iation4 ,"o       
specim5 has an exp&$ portion slightly   
ant]ior to t ( ! opposite angul>4 ,!    
articul> surface ne> ! po/]ior end has n
 be5 obs]v$2 ! po/]ior end ( ! angul>   
slopes (f abruptly4 ,! ant]ior sutures  
are se5 9 only two specim5s1 ,k4 ,u4    
nos4 #ghh1 #aadbe4 ,! d5t>y meets !     
angul> 9 a long oblique suture2 ! d5t>y 
gradually tap]s po/]odorsally & ends on 
! dorsal surface ( ! angul>4 ,! spl5ial 
fits into a po/]iorly direct$1 deep     
,v-%ap$ not* on ! v5tral surface4 ,!    
lat]ov5tral surface ( ! angul> conta9s  
s5sory pores ( ! m&ibul> l9e4 ,! v5tral 
surface ext5ds m$ially into a n>r[ %elf1
 approximately #a4j mm4 wide1 :i* ext5ds

 ! full l5g? ( ! bone2 ! ext]nal surface
 ( ?is %elf is smoo? & slightly concave 
dorsally4 ,ornam5tation ( ! angul>      
consi/s ( tub]cles & longitud9al or     
oblique /riae1 occurr+ mo/ly on ! exp&$ 
portion4 ,! m$ial surface is n se54     
,sev]al brok5 specim5s %[ a c5tral canal
 fill$ ) a rod ( calcite2 9 "o ( ^! !   
s5sory pores are also calcite-fill$ &   
appe> to be connect$ to ! rod4 ,?us !   
pores orig9ally op5$ into a c5tral      
canal4  ,! d5t>y is an unornam5t$ bone )
 ! ant]ior half curv+ m$ially2 ! greate/
 height is ant]ior4 ,?is bone 9 specim5 
,k4 ,u4 no4 #aadbe be>s irregul>ly      
spac$1 simple1 recurv$1 conical tee?2   
n9e 7 c\nt$1 b !re is space = _m o!rs4  
,"o o!r specim51 no4 #aadbi1 seems to h 
t9y tub]cles on ! surface4 ,! d5t>y     
meets ! spl5ial dorsally 9 a /raight    
suture4  ,! spl5ial also curves m$ially1
 & z /at$1 meets ! d5t>y 9 a /raight    
suture4 ,ornam5tation on ?is bone 0 n   
obs]v$4 ,! po/]ior m>g9 is ,v-%ap$ &    
fits ! not* 9 ! angul>4 ,! v5tral       

surface be>s ?ree or m s5sory pores ( ! 
m&ibul> l9e4  ,! gul> plates are oval4  
,! m$ial m>g9 is /raight to slightly    
curv$1 ! lat]al m>g9 curv$              
cresc5tically1 ! po/]ior end is blunt1 &
 ! ant]ior end some:at r\nd$4           
,ornam5tation v>ies greatly2 "s bones %[
 only a few tub]cles1 :]eas o!rs exhibit
 an almo/ conc5tric patt]n ( closely    
spac$ /riae4 ,typically !re are "s      
tub]cles 9 ! ant]ior qu>t] or ?ird ( !  
total l5g?2 ^! pass into longitud9ally  
ori5t$ /riae 9 ! po/]ior section4 ,a few
 h only r&omly ori5t$1 widely-spac$     
/riae4 ,! int]nal surface is smoo?4  ,! 
coronoid 7,k4 ,u4 no4 #aadbh7 is a      
triangul> bone1 ) ! apex po9t+ dorsally4
 ,! lat]al surface is smoo?2 no tee? 7  
obs]v$4 ,moy-,?omas 7#aicg3bib1 #bic7   
m5tions sev]al too?-be>+ coronoids 9    
,rhabdod]ma1 b z yet ^! h n be5 se5 9   
,synaptotylus4   ,axial skeleton  ,only 
?ree specim5s 7,k4 ,u4 nos4 #ghf;,f1    
#ghg;,f1 #aadej7 %[ p>ts ( ! v]tebral   
column1 b isolat$ neural & haemal ar*es 

are num]\s4 ,all are ( ! coelacan? type1
 hav+ ,y-%ap$ neural & haemal ar*es1 )\t
 c5tra4 ,a total c\nt ( #ch 0 obta9$1 b 
?is 0 incomplete2 ! actual numb] 0      
probably ne> #ej4 ,c\nts ( #aj & #af    
haemal ar*es 7 obta9$ 9 two ( !         
specim5s4 ,total height ( neural ar*es  
ranges f #g4e to #ab4j mm41 & ( haemal  
ar*es1 f #i4j to #ab4j mm4 ,! %ort]     
ar*es are ant]ior & ! height increases  
gradually to a maximum 9 ! caudal       
region4 ,height ( ! sp9es v>ies f #d4j  
to #i4j mm41 or f twice ! height ( ! ar*
 9 ! ant]ior to ?ree times ! height 9 ! 
caudal region4 ,total wid? ( ! base1    
measur$ 9 isolat$ specim5s because      
lat]al views 9 o!r specim5s prev5t$     
measur+ wid?1 ranges f #j4g to #d4b mm4 
,! %ort1 broad ar*es hav+ %ort sp9es    
occur at ! ant]ior end ( ! sp9al column2
 ! n>r[] ar*es hav+ tall sp9es occur    
t[>d ! caudal end4 ,brok5 neural &      
haemal ar*es %[ a ?9 cov]+ ( bone ) a   
c5tral1 calcite-fill$ cavity1 :i* 9 life
 may h be5 fill$ ) c>tilage 7,/5sioe1   

#aicb3eh1 fig4 #bj74  ,no ossifi$ ribs h
 be5 obs]v$1 ei!r isolat$ or 9 place4   
,= fur!r description ( ! axial skeleton1
 see ,hibb>d 7#aicc74  ,illu/ration3    
,,fig4 #f4 ,synaptotylus newelli        
7,hibb>d74 ,pair$ f9 girdles4 ,a1       
pectoral girdle1 lat]al view1 bas$ on   
,k4 ,u4 no4 #aadcc1 x #c4e4 ,b1 pelvic  
girdle basal plate1 m$ial 787 view1 bas$
 on ,k4 ,u4 no4 #ghh1 x #h4 ,ant]ior is 
t[>d ! left4   ,girdles & pair$ f9s  ,a 
ne>ly complete pectoral girdle on       
specim5 ,k4 ,u4 no4 #aadcc 7see fig4    
#f;,a7 has only a clei?rum & clavicle4  
,no evid5ce ( an extraclei?rum or       
supraclei?rum has be5 obs]v$1 b !       
extraclei?rum may be fus$ to ! clei?rum4
 ,! two bones =m a boot-%ap$ unit1 ) !  
ant]ov5tral "p turn$ m$ially to =m a    
horizontal process :i* meets ! opposite 
half ( ! girdle4 ,9 lat]al view !       
surface is unornam5t$1 & convex 9 !     
v5tral half4 ,! suture betwe5 ! clei?rum
 & clavicle beg9s on ! exp&$ po/]ior    
portion1 ! boot-heel1 at a po9t         

imm$iately bel[ ! greate/ wid? on !     
po/]ior m>g91 passes ant]iorly1 !n turns
 %>ply & p>allels ! ant]ior m>g94 ,!    
%ape ( ! clei?rum resembles t 9         
,rhabdod]ma & ! int]nal surface is n    
ridg$ 7see ,moy-,?omas1 #aicg3;fig4 #i74
 ,! exact ori5tation 9 ! fi% is unc]ta91
 b if ! m$ian ext5sion is really        
horizontal1 !n ! po/]ior expansion is   
direct$ caudally4 ,! m$ial surface is   
concave1 /eepe/ ne> ! ant]ior m>g91 & !n
 slopes outw>d ev5ly4 ,9 m$ial view "o  
specim5 7,k4 ,u4 no4 #aadbf7 %[s a      
small1 caudally direct$ projection (    
bone1 evid5tly = articulation ( !       
f9-skeleton1 at ! wide/ portion ( !     
clei?rum4 ,sutures on sev]al specim5s 7 
indi/9ct4 ,brok5 specim5s %[ sutural    
faces1 b _m ne>ly complete specim5s %[  
little or no indication ( sutures1 )\t  
reg>d to size ( ! girdles4 ,! int]nal   
/ructure ( ! f9 0 n obs]v$4  ,num]\s    
isolat$ basal plates ( ! pelvic girdle h
 reveal$ details ( /ructure b no        
in=mation on ! ori5tation4 ,presumably !

 basal plates ( ,synaptotylus _h        
ess5tially ! same ori5tation z ^? ( o!r 
coelacan?s 7,moy-,?omas1 #aicg3cie74 ,! 
mo/ complete basal plate is ,k4 ,u4 no4 
#ghh 7see fig4 #f;,b74 ,! ?ree apophyses
 div]ge ant]iorly2 ! horizontal "o is   
be/ develop$ & ! dorsal "o is lea/ well 
develop$4 ,a m$ian process 7,s*aeff]1   
#aieb3di71 d5ticulate on sev]al         
specim5s1 articulates ) ! correspond+   
process ( ! opposite plate4 ,! exp&$ "p 
t articulates ) ! skeleton ( ! f9 ext5ds
 caudally4 ,! po/]ior exp&$ "p is ne>ly 
squ>e 9 outl9e1 resembl+ ! dorsal1      
rectangul> projection4 ,"o side be>s    
ridges lead+ to ! extremities ( !       
apophyses1 & fa9t cr5ulations on ! m$ian
 process4 ,?is may be ! m$ial view4 ,!  
o!r view displays a smoo? surface1      
usually )\t indication ( ! ridges se5 9 
! rev]se view4 ,^! specim5s diff]       
some:at f ! basal plates ( ,rhabdod]ma &
 appe> to be int]m$iate betwe5          
,rhabdod]ma & ,coelacan?us 7,moy-,?omas1
 #aicg3;fig4 #aj;,a1 ,b74 ,! apophyses  

are n free z 9 ,rhabdod]ma b webb$ )    
bone almo/ to _! extremities1 z 9       
,coelacan?us4  ,! pelvic f9 is se5 9    
only two specim5s 7,k4 ,u4 nos4 #ghf;,f1
 #ghh74 ,t on no4 #ghh is lobate & has  
#be lepidotri*ia1 jo9t$ = approximately 
! di/al half1 & #b4e to #ac4j mm4 9     
l5g?4 ,total l5g? ( ! f9 is #be4j mm4   
,!re is no trace ( ! int]nal skeletal   
/ructure or ( ! articulation to ! basal 
plate 9 ei!r specim54 ,= a description (
 ! f9 on no4 #ghf;,f1 see ,hibb>d       
7#aicc3bha74   ,unpair$ f9s  ,a few     
isolat$ bones on ,k4 ,u4 no4 #ghh 7fig4 
#g7 are int]pret$ z basal plates ( !    
unpair$ f9s4 ,= additional description (
 ! unpair$ f9s on ! type1 ,k4 ,u4 no4   
#ghf;,f1 see ,hibb>d 7#aicc74  ,two ( ^!
 bones are flat1 smoo? & oblong1 be>+ a 
diagonal ridge t ext5ds 9 ! =m ( a      
projection4 ,ori5tation is completely   
unkn[n4 ,^! may be basal plates ( !     
ant]ior dorsal f94 ,! f9 on no4 #ghf;,f 
t ,hibb>d 7#aicc3bha7 int]pret$ z !     
po/]ior dorsal f9 is n[ ?\ght to be !   

ant]ior dorsal f94  ,illu/ration3 ,,fig4
 #g4 ,synaptotylus newelli 7,hibb>d74   
,basal plates ( unpair$ f9s4 ,a1 ant]ior
 dorsal f91 bas$ on ,k4 ,u4 no4 #ghh1 x 
#aj4 ,b1 po/]ior dorsal f91 bas$ on ,k4 
,u4 no4 #ghh1 x #ab4 ,c1 anal f91 bas$  
on ,k4 ,u4 no4 #aadej1 x #e4 ,ant]ior is
 t[>d ! left4  ,"o di/9ctive bone may   
repres5t ! basal plate ( ! po/]ior      
dorsal f94 ,?is incomplete specim5 %[s  
two project+ curv$ processes1 be>+ l[ b 
di/9ct ridges1 :i* div]ge1 probably     
ant]iorly4 ,! c5tral portion is n>r[4 ,!
 two ridges cont9ue onto ! po/]ior      
portion4 ,?is has be5 brok5 (f1 b %[s t 
! ridges div]ge aga94 ,! surface is     
smoo?1 except = ! ridges4 ,z be=e1      
ori5tation is unc]ta94 ,on no4 #ghf;,f  
?is f9 0 int]pret$ by ,hibb>d           
7#aicc3bha7 z ! anal f94  ,only "p ( "o 
basal plate ( ! anal f9 0 pres]v$ on ,k4
 ,u4 no4 #aadej4 ,t plate is oblong &   
has an exp&$ ant]ior end4 ,! n>r[1      
con/rict$ "p be>s two oblique ridges & a
 few tub]cles4 ,! po/]ior "p has ne>ly  

/raight m>g9s 7repres5t$ by impressions7
 & ! po/]ior m>g9 is oblique1 slop+     
ant]ov5trally4 ,! fl>$ ant]ior "p has a 
smoo? surface4 ,?is basal plate is m    
ne>ly l ^? ( ,coelacan?us1 accord+ to ! 
descriptions giv5 by ,moy-,?omas        
7#aicg3cii74 ,! basal plate is associat$
 ) sev5 app>5tly unjo9t$1 incomplete    
lepidotri*ia4 ,! anal f9 on no4 #ghf;,f 
is int]pret$ z ! ant]ior dorsal f9      
7,hibb>d1 #aicc3bha74  ,! caudal f9s are
 pres]v$ on ,k4 ,u4 nos4 #ghf;,f1       
#ghg;,f1 & h a total ( #bd lepidotri*ia1
 #ab above & #ab bel[4 ,^! are jo9t$ = !
 di/al half or two-?irds1 & are up to   
#af4j mm4 9 l5g?4 ,9 specim5 no4 #ghg;,f
 ! supplem5t>y caudal f9 has at lea/    
sev5 lepidotri*ia1 ! longe/ ( :i* is    
#aa4j mm4 b incomplete4 ,ant]ior        
lepidotri*ia appe> unjo9t$ b ! po/]ior  
ones are jo9t$ = ! di/al two-?irds 787  
7^! are brok5 (f74 ,! supplem5t>y caudal
 f9 is approximately #a4e mm4 long &    
#h4j mm4 or m wide4 ,! supplem5t>y      
caudal f9 on ,k4 ,u4 no4 #ghf;,f        

describ$ by ,hibb>d 7#aicc3bha7 c\ld n  
be obs]v$2 ?is "p ( ! caudal f9 is      
miss+4   ,squamation  ,9 ! suite (      
specim5s isolat$ scales are num]\s1 b   
pat*es ( scales are r>e4 ,only two      
specim5s 7,k4 ,u4 nos4 #ghf;,f1 #ghg;,f7
 are complete en\gh = scale c\nts1 b    
pres]vation p]mits only p>tial c\nts4 ,9
 g5]al ! scales resemble ^? (           
,rhabdod]ma elegans 7,newb]ry74  ,!     
scales are oval4 ,! expos$ po/]ior "p ( 
ea* be>s po/]iorly conv]g+ ridges2 !    
ant]ior "p is wide/ & %[s a f9e fibrill>
 /ructure4 ,!re are at lea/ six         
scale-r[s on ei!r side ( ! lat]al l9e4  
,lat]al l9e scales %[ no pores1 & except
 = slight irregul>ities 9 ! ori5tation &
 l5g? ( ! po/]ior ridges1 closely       
resemble ! o!rs4 ,c5tral ridges on !    
lat]al l9e scales are %ort] & t5d to    
div]ge f ! c5t] ( ! impression ( !      
canal4 ,! lat]al l9e canal %[s only z ! 
impression ( a cont9u\s canal #j4g mm4 9
 diamet]4 ,pres]vation is poore/ 9      
scales along ! l9e ( ! neural & haemal  

ar*es2 !re=e lat]al l9e scales are r>ely
 pres]v$4 ,isolat$ scales are ( two     
types3 ^? on :i* ! po/]ior ridges       
conv]ge %>ply & =m ! go?ic ar*          
configuration m5tion$ by ,hibb>d        
7#aicc3bhb71 & ^? :i* d n4 ,bo? types ( 
scales c be pres5t on "o fi%1 z %[n by  
specim5 no4 #ghh4 ,?is is n app>5t on   
nos4 #ghf;,f & #ghg;,f2 all ( ! scales  
on ^! specim5s appe> to be mu* alike4   
,bo? ,moy-,?omas 7#aicg3che7 & ,s*aeff] 
7#aieb3ea1 #eb7 h rem>k$ on ! v>iation (
 ! scales on diff]5t p>ts ( ! same fi%4 
,because ! numb] ( ridges & am\nt (     
conv]g5ce ( ! ridges is n relat$ to size
 ( ! scale1 x is conclud$ t ^! *>act]s  
are n ( taxonomic significance4  ,!     
/rong resemblance ( ! scales ( ! ,g>nett
 specim5s to ^? ( ,rhabdod]ma elegans   
7,newb]ry7 caus$ ,moy-,?omas 7#aicg3cii7
 to add ,hibb>d's two species to !      
synonymy ( ,r4 elegans4 ,b at t "t only 
! scales c\ld be adequately describ$4   
,if ! %ape ( ! scale & ! numb] & patt]n 
( ridges c v>y ) age1 size & %ape ( !   

scale1 x foll[s t assignm5t ( isolat$   
scales to a species %\ld n be attempt$4 
,assignm5t to g5us %\ld be made only )  
caution4  ,discussion4--,! relation%ip (
 ,synaptotylus to o!r coelacan?s is     
obscure at pres5t4 ,! knoblike antotic  
processes on ! basisph5oid are unlike ^?
 ( any o!r kn[n coelacan?4 ,!           
palatoquadrate complex is %ap$ l t (    
,rhabdod]ma elegans b consi/s ( few]    
bones1 probably because ( fusion4 ,!    
scales resemble ^? ( ,rhabdod]ma4 ,)    
reg>d to g5]al %ape ( f9 girdles1 !     
pectoral girdle resembles t (           
,eu/h5opt]on m ?an t ( ,rhabdod]ma1 b ! 
clei?rum is m ne>ly l ! clei?rum (      
,rhabdod]ma4 ,! pelvic girdle appe>s to 
be midway betwe5 ^? ( ,rhabdod]ma &     
,coelacan?us 9 g5]al appe>ance4 ,reg>d+ 
! basal plates ( ! rema9+ f9s1 ^? (     
,synaptotylus appe> to resemble basal   
plates ( bo? ,rhabdod]ma & ,coelacan?us4
 ,consid]+ ! /ructure ( ! sph5e?moid    
region ( ! bra9case1 ,synaptotylus is   
probably m closely relat$ to ,rhabdod]ma

 ?an to o!r kn[n coelacan? g5]a4        
,,comm5ts ,,on ,,classifications        
,classification ( ,c>bonif]\s coelacan?s
 has be5 difficult1 p>tly because !     
rema9s are commonly fragm5t>y1 &        
significant *anges 9 anatomy did n      
become app>5t 9 e>ly /udies4 ,9 g5]al1  
coelacan?s h be5 rem>kably /able 9 mo/  
*>act]s1 & x has be5 difficult to divide
 ! gr\p into families4 ,z ,s*aeff]      
7#aieb3ef7 po9t$ out1 def9ition (       
coelacan? g5]a & species has previ\sly  
be5 made on non-m]i/ic *>act]s1 & !     
range ( v>iation )9 a species has       
receiv$ little att5tion4 ,= example1    
,reis 7#ahhh3ga7 e/abli%$ ! g5us        
,rhabdod]ma1 us+ ! /rong /riation ( !   
scales1 gul> plates & po/]ior m&ible z !
 ma9 *>act]s ( ?is ,c>bonif]\s g5us4    
,moy-,?omas 7#aicg3cii-daa7 ref]r$ all  
,c>bonif]\s species to ,rhabdod]ma1     
r$escrib$ ! g5us & comp>$ x to          
,coelacan?us1 ! ,p]mian g5us4 ,he cit$ z
 specific *>act]s ! ornam5tation ( !    
angul>s1 op]cul>s & gul> plates         

7,moy-,?omas1 #aice3ci2 #aicg3che74     
,individual v>iation 9 "s species has   
r5d]$ ornam5tation a poor crit]ion4 ,?is
 v>iation is app>5t 9 ,synaptotylus     
newelli 7,hibb>d71 "s specim5s hav+     
little or no ornam5tation2 o!rs hav+ mu*
 m4 ,! numb] ( ridges & patt]n ( ridges 
on ! scales also v>ies4 ,s*aeff]        
7#aieb3ef7 has f\nd ?is to be true (    
,diplurus also4 ,moy-,?omas 7#aice3dj2  
#aicg3che7 realiz$ t ! type ( scale is a
 poor crit]ion = specific diff]5tiation4
 ,9 ! se>* = features useful 9 di/+ui%+ 
g5]a ( coelacan?s1 ,s*aeff] & ,gregory  
7#aifa3c1 #g7 f\nd ! /ructure ( !       
basisph5oid to be di/9ctive 9 kn[n g5]a1
 & ?\ght x _h taxonomic significance at 
?is level4 ,high] categories %\ld h z _!
 basis *>act]s t display evolution>y    
sequ5ces4 ,a rec5t classification 7,b]g1
 #aidj71 foll[$ 9 ?is pap]1 reflects two
 evolution>y tr5ds 9 endocranial        
/ructure ( coelacan?s3 r$uction (       
endocranial ossification & loss ( !     
basipt]ygoid processes4 ,because !re has

 be5 little *ange 9 o!r /ructures 9     
coelacan?s1 ,b]g's classification is !  
mo/ useful4 ,b]g 7#aidj3cij7 includes   
,rhabdod]ma 9 ! subord] ,diploc]cidoidei
 because ( ! pres5ce ( ! basipt]ygoid   
processes1 & 9 ! s+le family1           
,diploc]cidae1 b rem>ks t because ( !   
r$uc$ am\nt ( endocranial ossification !
 ,c>bonif]\s ,diploc]cidae probably     
con/itute a di/9ct family4 ,9 consid]+  
?is concept ( classification1 !         
subfamilies ,diploc]c9ae &              
,rhabdod]mat9ae ( ! family ,diploc]cidae
 are propos$ above4 ,! subfamily        
,rhabdod]mat9ae includes at pres5t      
,rhabdod]ma & ,synaptotylus4 ,! pr9cipal
 *>act]s ( ! subfamily ,rhabdod]mat9ae1 
nam$ = ! fir/ kn[n g5us1 are ! ret5tion 
( ! basipt]ygoid processes & ! r$uction 
( endocranial ossification4 ,application
 ( ?is classification bas$ ^u           
endocranial /ructure w\ld probably *ange
 exi/+ gr\p+s ( species ( ,c>bonif]\s   
coelacan?s2 ! entire complex (          
,c>bonif]\s g5]a %\ld be r$escrib$ &    

r$ef9$4 ,x w be necess>y to consid]     
endocranial /ructure 9 any future       
classification4  ,! great] "p ( !       
evolution previ\sly m5tion$ appe>s to h 
be5 accompli%$ dur+ ! ,c>bonif]\s2      
!reaft] coelacan? /ructure became       
/abiliz$4 ,! tr5d progress$ f ,devonian 
coelacan?s :i* _h two l>ge unpair$ bones
 9 ! endocranium1 & bo? antotic &       
basipt]ygoid processes on ! basisph5oid1
 to ,c>bonif]\s fi%es 9 :i* ossification
 0 r$uc$ to a numb] ( pair$ & unpair$   
bones emb$d$ 9 c>tilage1 & reta9+ bo?   
processes1 & !n po/-,c>bonif]\s k9ds )  
r$uc$ ossification & no basipt]ygoid    
processes4 ,! ,p5nsylvanian 0 evid5tly !
 "t ( greate/ *ange = ! coelacan?s1 & !y
 h n *ang$ significantly s9ce1 9 spite (
 ! fact t s9ce ! ,jurassic !y h %ift$ _!
 environm5t f %all[1 fre% wat] to       
mod]ate dep? 9 ! sea 7,s*aeff]1         
#aiec3;fig4 #a74 ,! *anges 9 endocranial
 /ructure appe> to be significant1 & are
 p]haps relat$ to high] effici5cy ( !   
m\? p>ts 9 cat*+ & swall[+ prey 7see p4 

#dhb74   ,,environm5t  ,! coelacan?     
fi%es f ! ,rock ,lake %ale are "p ( !   
v>i$ fauna collect$ f ,g>nett4 ,peabody 
7#aieb3ch7 li/$ _m elem5ts ( ! fauna &  
flora1 & conclud$ t ! deposits are (    
lagoonal orig94 ,9 addition to num]\s   
inv]tebrates 7includ+ micr(ossils7 &    
ar?ropods1 a numb] ( v]tebrates o!r ?an 
coelacan?s h be5 f\nd4 ,^! include at   
lea/ "o k9d ( %>k1 ,hesp]oh]peton       
g>nett5se ,peabody1 "o or m k9ds (      
undescrib$ labyr9?odonts & ! reptiles   
,petrolacosaurus kans5sis ,lane1        
,edaphosaurus ecordi ,peabody1 &        
,clepsydrops 7undescrib$ species74 ,?is 
is inde$ a ri* v]tebrate fauna1 & !     
e>lie/ kn[n reptilian fauna4 ,mu* ( !   
rock conta9s plant rema9s4 ,! flora t   
has be5 id5tifi$ is adapt$ to gr[+ 9 a  
well-dra9$ soil2 al?\gh x conta9s "s    
elem5ts consid]$ *>act]i/ic ( ! ,p]mian1
 x is ( ,p5nsylvanian age 7,moore et    
al41 #aicf74 ,peabody 7#aieb3ch-ci7     
discusses ! features ( ^! lagoonal      
s$im5ts4 ,mu* ( ! fauna & flora sugge/s 

cont95tal orig91 b ! _m m>9e            
inv]tebrates at "s horizons indicate t  
at lea/ "s ( ! s$im5ts 7 ( m>9e orig94  
,little c be said ab\t ! actual         
environm5t ( ! liv+ fi%es ( ! g5us      
,synaptotylus4 ,rema9s ( ^! fi%es occur 
9 lay]s conta9+ m>9e inv]tebrates1 z    
well z 9 ^? conta9+ plant rema9s &      
v]tebrate skeletal p>ts1 & 9 ^? ne>ly   
completely compos$ ( d>k c>bonace\s     
mat]ial4 ,mo/ ( ! rema9s are fragm5t>y &
 consi/ ( isolat$ bones1 isolat$ scales1
 & dissociat$ skulls2 only "o specim5 & 
half ( ano!r are ne>ly complete4 ,_m    
publi%$ /atem5ts on ,rhabdod]ma1 a      
relat$ g5us1 indicate bo? m>9e &        
fre%-wat] environm5ts4 ,wehrli          
7#aica3aae7 reg>d$ ,rhabdod]ma elegans  
7,newb]ry7 z a euryhal9e species1 & cit$
 its occurr5ce ) bo? m>9e & fre%-wat]   
fossils4 ,ald+] 7#aica3aii7 also f\nd   
?is to be ! case ) o!r species1 & ,fiege
 7#aiea3ag7 quotes o!rs z giv+ ! same   
in=mation4 ,kell] 7#aicd3iac7 ?\ght t   
few ,c>bonif]\s fi%es 7 exclusively     

m>9e1 & /at$ t ! majority ( !m became   
adapt$ to fre% wat] dur+ ! late         
,c>bonif]\s4 ,lat]1 ,s*aeff] 7#aiec3age7
 /at$ t all ,c>bonif]\s & ,p]mian       
coelacan?s 7 fre%-wat] fi%es1 & t _m 7 f
 swamp deposits4 ,if ,kell] is correct1 
!n memb]s ( ! g5us ,synaptotylus may h  
inhabit$ ! lagoon1 ! adjac5t sea1 or !  
/reams dra9+ into ! lagoon4 ,p]haps ^!  
fi%es swam up/ream1 z mod]n salmon &    
t>pon d1 al?\gh !re is no direct evid5ce
 = ?is4 ,possibly !y liv$ 9 ! lagoon at 
times ( scant ra9fall & little run(f1 :5
 ! sal9ity ( lagoon wat] approa*$ normal
 m>9e values or ! fi%es may h liv$ 9 !  
/reams1 & aft] dea? 7 wa%$ into !       
lagoon4 ,z num]\s rema9s ( l& plants &  
animals 7 wa%$ 91 p]haps ?is be/ acc\nts
 = ! pres5ce ( ! fi% 9 ne>ly all lay]s (
 ! deposits1 n only ! m>9e /rata4       
,,summ>y  ,a new g5us ( ,p5nsylvanian   
coelacan?s1 ,synaptotylus1 is describ$ &
 a previ\sly nam$ species1 ,coelacan?us 
newelli ,hibb>d1 #aicc 7,c4 arcuatus    
,hibb>d1 #aicc1 is a junior synonym71 is

 ref]r$ to ?is g5us4 ,all specim5s (    
,synaptotylus newelli 7,hibb>d7 7       
collect$ f ! ,rock ,lake %ale memb] ( ! 
,/anton =mation1 ,lans+ gr\p1 ,miss\ri  
s]ies1 six miles nor?we/ ( ,g>nett1     
,&]son ,c\nty1 ,kansas4 ,synaptotylus is
 di/+ui%$ f all o!r coelacan?s by a     
basisph5oid hav+ l>ge1 knoblike antotic 
processes ea* connect$ by a l[ ridge to 
a small basipt]ygoid process4           
,synaptotylus is mo/ closely relat$ to  
,rhabdod]ma1 b is int]m$iate betwe5     
,rhabdod]ma & ,coelacan?us 9 %ape ( ! f9
 girdles & basal plates4 ,two new       
subfamilies1 ,diploc]c9ae &             
,rhabdod]mat9ae1 ( ! family             
,diploc]cidae1 are propos$4             
,synaptotylus & ,rhabdod]ma are includ$ 
9 ! subfamily ,rhabdod]mat9ae1 because  
bo? exhibit r$uc$ ossification 9 !      
endocranium & reta9 basipt]ygoid        
processes4  ,loss ( ! basipt]ygoid      
processes 9 po/-,c>bonif]\s coelacan?s  
may reflect ! developm5t ( a m effici5t 
fe$+ me*anism1 by all[+ ! palatoquadrate

 complex & m&ible to sw+ f>!r lat]ally &
 exp& ! oral cavity4  ,synaptotylus     
newelli 7,hibb>d7 may h occupi$ ei!r !  
sea or fre% wat]2 ^! fi%es occur 9      
lagoonal deposits ) reptiles &          
amphibians1 ar?ropods1 m>9e inv]tebrates
 & rema9s ( l& plants4  ,because scale  
patt]ns on ,synaptotylus & ,rhabdod]ma  
are s ne>ly simil> & v>y ) size ( !     
scale & its location on ! fi%1 x is     
recomm5d$ t isolat$ scales n be assign$ 
to a species1 & to a g5us only ) great  
caution4     ,,lit]ature ,,cit$         
,,ald+]1 ,h4  #aica4 ,ueb] k>bonis*e    
,fis*e aus ,we/fael54 ,paleont4 ,zeit41 
#ac3ahf-bja4   ,,b]g1 ,l4 ,s4  #aidj4   
,classification ( fi%es1 bo? ,rec5t &   
fossil4 ,mosc[ & ,l5+rad1 #aidj 7,j4 ,w4
 ,edw>ds1 ,ann ,arbor1 ,mi*igan1 #aidg1 
(fset reproduction1 pp4 #a-cde1 #aig    
figs41 plus ,engli% translation ( text1 
pp4 #cdf-eag1 #aidg47   ,,fiege1 ,k4    
#aiea4 ,e9e ,fis*-,s*wimmspur aus dem   
,culm bei ,waldeck4 ,neues ,jahrb4      
,geol4 & ,palaeont4 ,jahrgang           

#aiea3i-ca4   ,,hibb>d1 ,c4 ,w4  #aicc4 
,two new species ( ,coelacan?us f !     
middle ,p5nsylvanian ( ,&]son ,c\nty1   
,kansas4 ,kansas ,univ4 ,sci4 ,bull41   
#ba3bgi-bhg4   ,,kell]1 ,g4  #aicd4     
,fis*re/e aus dem ob]k>bon des          
,ruhrgebiets4 ,gluckauf1 #gj3iac-iag4   
,,moore1 ,r4 ,c41 ,,elias1 ,m4 ,k41 &   
,,newell1 ,n4 ,d4  #aicf4 ,a ,p]mian    
flora f ! ,p5nsylvanian rocks ( ,kansas4
 ,j\r4 ,geol41 #dd3a-ca4                
,,moy-,,?omas1 ,j4 ,a4  #aice4 ,a       
synopsis ( ! coelacan? fi%es ( !        
,york%ire ,coal ,measures4 ,ann4 ,mag4  
,nat4 ,hi/41 #ae 7s]4 #aj73 #cg-df4     
#aicg4 ,! ,c>bonif]\s coelacan? fi%es ( 
,great ,brita9 & ,irel&4 ,proc4 ,zool4  
,soc4 ,london1 #ajg 7,b73 #chc-dae4     
,,peabody1 ,f4 ,e4  #aieb4              
,petrolacosaurus kans5sis ,lane1 a      
,p5nsylvanian reptile f ,kansas4 ,kansas
 ,univ4 ,paleont4 ,contrib41 #a3a-da4   
,,reis1 ,o4 ,m4  #ahhh4 ,die            
,coelacan?95 mit besond]5               
,b]uecksi*tigung d] im ,weiss5 ,jura    

,bay]ns v]komm5d5 ,art54                
,palaeontographica1 #ce3a-if4           
,,s*aeff]1 ,b4  #aieb4 ,! ,triassic     
coelacan? fi% ,diplurus1 ) obs]vations  
on ! evolution ( ! ,coelacan?9i4 ,bull4 
,am]4 ,mus4 ,nat4 ,hi/41 #ii3;art4 #b1  
#bi-gh4  #aiec4 ,latim]ia & ! hi/ory ( !
 coelacan? fi%es4 ,new ,york ,acad4     
,sci4 ,trans41 7#b7 #ae3agj-agh4        
,,s*aeff]1 ,b41 & ,,gregory1 ,j4 ,t4    
#aifa4 ,coelacan? fi%es f ! cont95tal   
,triassic ( ! we/]n ,unit$ ,/ates4 ,am]4
 ,mus4 ,novitates1 #bjcf3a-ah4          
,,s*aeff]1 ,b41 & ,,ros51 ,d4 ,e4       
#aifa4 ,major adaptive levels 9 !       
evolution ( ! act9opt]ygian fe$+        
me*anism4 ,am4 ,zool41 #a3ahg-bjd4      
,,smi?1 ,j4 ,l4 ,b4  #aici4 ,a liv+     
coelacan?id fi% f ,s\? ,africa4 ,trans4 
,roy4 ,soc4 ,s\? ,africa1 #bh3a-ajf4    
,s,t,e,n,s,i,oe1 ,e4 ,a4  #aiba4        
,triassic fi%es f ,spitzb]g54 ,"p ,i4   
,vi5na1 ,adolf ,holzhaus53 #a-cjg4      
#aicb4 ,triassic fi%es f ,ea/ ,gre5l&4  
,m$del4 om ,gronl&1 #ch3a-cje4          

,,t*]nav91 ,v4 ,v4  #aidh4 ,on !        
me*anical work+ ( ! head ( bony fi%es4  
,proc4 ,zool4 ,soc4 ,london1            
#aah3abi-adc4   ,,wehrli1 ,h4  #aica4   
,die ,fauna d] ,we/faelis*5 ,/uf5 ,a und
 ,b d] ,bo*um] ,mulde zwis*5 ,dortmund  
und ,kam5 7,we/fael574                  
,palaeontographica1 #gd3ic-acd4         
,transmitt$ ,m>* #bi1 #aifb4