,univ]sity ( ,kansas ,publications ,museum ( ,natural ,hi/ory ,volume #ab1 ,no4 #b1 pp4 #aee-ahj1 #aj figs4 -----------,july #aj1 #aiei--------------- ,! ,ance/ry ( ,mod]n ,amphibia3 ,a ,review ( ! ,evid5ce ,,by ,,!odore ,h4 ,,eaton1 ,,jr4 ,univ]sity ( ,kansas ,lawr5ce #aiei ,univ]sity ( ,kansas ,publications1 ,museum ( ,natural ,hi/ory ,editors3 ,e4 ,raymond ,hall1 ,*airman1 ,h5ry ,s4 ,fit*1 ,rob]t ,w4 ,wilson ,volume #ab1 ,no4 #b1 pp4 #aee-ahj ,publi%$ ,july #aj1 #aiei ,univ]sity ( ,kansas ,lawr5ce1 ,kansas ,,pr9t$ ,,9 ,,! ,,/ate ,,pr9t+ ,,plant ,,topeka1 ,,kansas #aiei ,illu/ration #bg-hcfb ,transcrib]'s ,notes3 ,sev]al typos h be5 regulat$4 ,"o typo ( ance/] = ance/or 0 correct$4 ,"o in/ance ( salam&]like correct$ to salaman]-l4 ,! ,ance/ry ( ,mod]n ,amphibia3 ,a ,review ( ! ,evid5ce ,,by ,,!odore ,h4 ,,eaton1 ,,jr4 ,,introduction ,9 try+ to det]m9e ! ance/ral relation%ips ( mod]n ord]s ( ,amphibia x is n possible to select satisfactory /ructural ance/ors among a weal? ( fossils1 s9ce v few ( ! kn[n fossils c\ld ev5 be consid]$ possible1 & sc>cely any are satisfactory1 = su* a selection4 ,! ne>e/ approa* ?us f> to a solution ( ! problem 9 ?is mann] has be5 made ) ref]5ce to ! ,anura4 ,watson's pap] 7#aidj71 ) c]ta9 modifications made necess>y by ,gregory 7#aiej71 provides ! paleontological evid5ce s f> available on ! orig9 ( frogs4 ,x %[s t sev]al features ( ! skeleton ( frogs1 su* z ! enl>gem5t ( ! int]pt]ygoid spaces & orbits1 r$uction ( ! m po/]ior d]mal bones ( ! skull1 & d[nw>d spread ( ! neural ar*es lat]al to ! noto*ord1 7 already app>5t 9 ! ,p5nsylvanian ,amphibamus 7,fig4 #a71 ) :i* ,gregory synonymiz$ ,miobatra*us & ,mazon]peton4 ,b betwe5 ! ,p5nsylvanian & ! ,triassic 7! age ( ! e>lie/ kn[n frog1 ,protobatra*us7 !re 0 a great lapse ( "t1 & t :i* pass$ betwe5 any conceivable ,paleozoic ance/or ( ,urodela & ! e>lie/ satisfactory repres5tative ( ?is ord] 79 ! ,cretace\s7 0 mu* long] /ill4 ,! ,apoda1 s f> z kn[n1 h no fossil record4 ,nev]!less x %\ld be possible1 fir/1 to survey ^? *>act]s ( mod]n ,amphibia t might af=d "s comp>ison ) ! e>ly fossils1 & second1 to discov] among ! kn[n ,paleozoic k9ds ^? :i* are suffici5tly unspecializ$ to p]mit d]ivation ( ! mod]n patt]ns4 ,fur!r circum/antial evid5ce may be obta9$ by exam9+ "s features ( ,rec5t ,amphibia :i* c\ld n readily be comp>$ ) any?+ 9 ! fossils2 su* are ! embryonic developm5t ( ! s(t /ructures1 includ+ c>tilag9\s /ages ( ! skeleton1 ! developm5t & v>i\s specializations ( ! e> me*anism1 adaptive *>act]s associat$ ) aquatic & t]re/rial life1 & s on4 ,,comp>ison ,,( ,,mod]n ,,ord]s ,,) ,,! ,,labyr9?odonts ,,& ,,lepospondyls ,illu/ration3 ,fig4 #a4 ,saur]peton 7x #a_/b1 aft] ,rom]1 #aicj1 fig4 #f72 ,amphibamus1 ! palatal view x #b-a_/d1 f ,watson1 #aidj1 fig4 #d 7z ,miobatra*us71 ! dorsal view x #b-a_/b1 f ,gregory's revis$ figure ( ,amphibamus 7#aiej1 ,fig4 #a72 ,protobatra*us1 x #a1 f ,watson1 #aidj1 fig4 #ah1 #ai4 ,9 bo? ,anura & ,urodela ! skull is %ort1 broad1 relatively flat1 ) r$uc$ pt]ygoids t div]ge lat]ally f ! p>asph5oids leav+ l>ge int]pt]ygoid vacuities1 & ) l>ge orbits4 7,^! /atem5ts d n apply to c]ta9 l>val or p]5nibran*iate =ms47 ,! skull 9 bo? ord]s has lo/ a numb] ( primitive d]mal bones 9 ! po/]ior "p2 ^! are3 basioccipital1 supraoccipital1 po/p>ietal1 int]temporal1 supratemporal1 & tabul>4 ,! exoccipitals =m ! two condyles b !re are no =am9a = ! #aa? & #ab? n]ves1 s9ce ^! are n sep>ate 9 mod]n ,amphibia4 ,! opi/hotic is miss+ 9 all except ,proteidae 7b see discussion ( ! e>74 ,al?\gh ! skull is normally auto/ylic1 a movable basipt]ygoid articulation is pres5t among ,hynobiid salam&]s & 9 at lea/ ! metamorphic /ages ( primitive frogs1 & !re=e %\ld be expect$ 9 _! ance/ors4 ,! v]tebrae are1 ( c\rse1 complete2 see discussion 9 lat] section4 ,! quadratojugal1 lo/ 9 salam&]s1 is reta9$ 9 frogs1 & conv]sely ! lacrimal1 abs5t 9 frogs1 occurs 9 a few primitive salam&]s4 ,! situation 9 ,apoda is diff]5t1 b po/frontal & jugal %\ld be not$ z bones reta9$ 9 ?is ord] :ile lo/ 9 ! o!rs4 ,?us1 9 spite ( m9or diff]5ces1 ! above li/ %[s t !re are num]\s & detail$ simil>ities betwe5 ,anura & ,urodela ) respect to ! features 9 :i* !y diff] f ! ,paleozoic ord]s4 ,pusey 7#aidc7 li/$ #bf *>act]s :i* ,ascaphus %>es ) salam&]s b n ) m advanc$ frogs2 a few ( ^! might be co9cid5tal1 b mo/ ( !m are ( "s complexity & mu/ be tak5 to indicate relation%ip4 ,! ma9 adaptive specializations ( ,anura1 h[ev]1 includ+ loss ( ! adult tail1 extreme r$uction 9 numb] ( v]tebrae1 =mation ( uro/yle1 elongation ( ! ilium & l5g!n+ ( ! h9d legs1 mu/ h appe>$ at a lat] "t ?an ! sep>ation ( t ord] f any possible common /em ) ,urodela1 al?\gh !y are only p>tially develop$ 9 ! ,triassic ,protobatra*us4 ,turn+ to ! ,paleozoic ,amphibia1 !re are two gr\ps 9 :i* "s likelihood ( a relation%ip ) mod]n ord] exi/s4 ,9 ! ,p5nsylvanian ,trim]orha*oidea 7,labyr9?odontia1 ord] ,temnospondyli7 "s memb]s1 su* z ,eugyr9us1 ,saur]peton1 & notably ,amphibamus 7,fig4 #a7 _h %ort1 broad heads1 an expansion ( palatal & orbital op5+s1 po/]ior wid5+ ( ! p>asph5oid associat$ ) div]g5ce ( ! pt]ygoids1 a movable basipt]ygoid articulation1 & r$uction 9 size 7b n loss7 ( ! m po/]ior d]mal bones ( ! skull4 ,9 recognition ( ,watson's 7#aidj7 evid5ce t ^! animals make q suitable /ructural ance/ors ( frogs1 ,rom] 7#aide7 plac$ ,amphibamus 9 an ord]1 ,eoanura1 b ,gregory 7#aiej7 indicat$ t x might bett] be left ) ! temnospondyls4 ,association ( ! urodele /em ) ?is gr\p does n seem to h be5 propos$ hi!rto4 ,! o!r gr\p ( ,paleozoic ,amphibia t has be5 consid]$ probably ance/ral to any mod]n type is ! subclass ,lepospondyli1 conta9+ ?ree ord]s1 ,ai/opoda1 ,nectridia & ,microsauria4 ,9 ^! ! v]tebrae are complete 7holospondyl\s71 ! c5tra presumably =m$ by cyl9drical ossification ar\nd ! noto*ord1 & !re is no evid5ce z to ! contributions f embryonic c>tilage units4 ,x is important to note at ?is po9t t precisely ! same /atem5t c be made reg>d+ ! v]tebrae ( adults ( all ?ree ,rec5t ord]s1 yet = all ( !m1 z %[n 9 a lat] section1 we h ample evid5ce ( ! "p play$ by c>tilage elem5ts 9 v]tebral developm5t4 ,!re=e 7a7 we _c say t !re 7 no su* elem5ts 9 embryonic /ages ( lepospondyls1 & 7b7 x w\ld take m ?an ! evid5ce f adult v]tebrae to relate a p>ticul> mod]n ord] 7= example1 ,urodela7 to ! ,lepospondyli4 ,vague simil>ities to ,urodela h be5 not$ by _m au?ors 9 ! ,nectridia1 ,ai/opoda & ,microsauria1 b ^! are n detail$ & ref] ma9ly to ! v]tebrae4 ,! skulls d n %[1 ei!r dorsally or 9 ! palate1 any /rik+ resemblance to ^? ( g5]aliz$ salam&]s1 & c]ta9ly mo/ kn[n lepospondyls are too specializ$ to s]ve z ! s\rce ( ,urodela4 ,x is true t ! elongate bodies1 small limbs1 & app>5t aquatic habitus ( "s lepospondyls accord well ) our usual picture ( a salam&]1 b su* a =m & way ( life h appe>$ 9 _m e>ly ,amphibia1 includ+ ! labyr9?odonts4 ,! family ,lysorophidae 7,fig4 #b71 usually plac$ among microsaurs1 is suffici5tly close 9 skull /ructure to ! ,apoda to be a possible ance/or ( ^!1 b x probably has no?+ to d ) ,urodela1 by reason ( ! num]\s morphological specializations t 7 associat$ ) its snakelike habitus4 ,illu/ration3 ,fig4 #b4 ,lysorophus tric>9atus1 lat]al & po/]ior views x #b-a_/b1 modifi$ aft] ,sollas1 #aibj1 ,figs4 #h & #ab1 respectively2 palatal view aft] ,broom1 #aiah1 x #a-a_/b4 ,= explanation ( abbreviations see ,fig4 #c4 ,mc,dowell's 7#aieh7 sugge/ion t x w\ld be pr(itable to look among ! ,seym\riamorpha = ! ance/ors ( frogs seems to be bas$ ^u a few details ( app>5t resemblance r ?an a compreh5sive view ( ! major *>act]s ( ! animals4 ,9 mo/ po9ts :i* he m5tions 7limb girdles1 =m ( e>1 pt]ygoid articulation7 ! pres5t writ] does n see a clos] simil>ity ( frogs to ,seym\riamorpha ?an to ,temnospondyli4 ,/ill o!r op9ions h be5 express$4 ,h]re 7#aice71 = in/ance1 concludes on anatomical1 biological & paleontological gr\nds t ! ord]s ( ,urodela1 ,anura1 ,apoda & ,/egocephali 7 all indep5d5tly evolv$ f fi%1 b beyond cit+ ! op9ions ( a numb] ( o!r au?ors he does n pres5t tangible evid5ce = ?is extreme polyphyletic int]pretation4 ,m notable are ! views ( sev]al ,sc&9avian work]s 7,saeve-,so$]b]gh1 #aicd2 ,j>vik1 #aidb2 ,holmgr51 #aicc1 #aici1 #aidi;a1 b71 ( :om ,j>vik1 9 a ?or\gh analysis ( ! e?moid region1 w\ld d]ive ! ,urodela f ,porolepid ,crossopt]ygii1 & all o!r tetrapods f ! ,rhipidi/ia2 ,saeve-,so$]b]gh & ,holmgr51 ! latt] us+ ! /ructure ( c>pus & t>sus1 see a relation%ip ( ,urodela to ,dipnoi1 b accept ! d]ivation ( labyr9?odonts & o!r tetrapods f ,rhipidi/ia4 ,all ( ?is "w is mo/ detail$ & labori\s1 & has produc$ a great quantity ( data useful to morphologi/s1 b ! diphyletic !ory is n widely adopt$2 ! evid5ce adduc$ = x seems to consi/ l>gely ( m9utiae :i*1 tak5 by !mselves1 are inconclusive1 or l5d !mselves to o!r int]pretation4 ,= in/ance ,holmgr5's num]\s figures ( embryonic limbs ( salam&]s %[ patt]ns ( c>tilage elem5ts t he w\ld trace to ! ,dipnoan type ( f91 yet x is difficult to see t ! weight ( evid5ce requires ?is1 :5 ! patt]n does n diff] 9 any fundam5tal mann] f ^? se5 9 o!r embryonic tetrapods1 & ! diff]5ces t d appe> may well be tak5 to h ontog5etic r ?an phylog5etic mean+4 ,fur!r1 ! ,dipnoan specialization ( d5tal plates & auto/ylic jaw susp5sion1 already accompli%$ e>ly 9 ! ,devonian1 w\ld seem to exclude ,dipnoi f possible ance/ry ( ! ,urodela1 an ord] unkn[n prior to ! ,mesozoic1 9 :i* ! tee? are ess5tially simil> to ^? ( late ,paleozoic ,amphibia1 & ! jaw susp5sion is n yet 9 all memb]s auto/ylic4 ,,! ,,e> ,illu/ration3 ,fig4 #c4 ,occipital region ( skulls ( ,megalocephalus brevicornis 7x #c_/aj1 aft] ,watson1 #aibf1 z ,or?osaurus71 ,dv9osaurus 7x #a_/d1 modifi$ aft] ,by/r[1 #aich2 ! l[] figure aft] ,su%k91 #aicf71 & ,necturus maculosus 7x #c1 orig9al1 f ,k4 ,u41 ,no4 #cdga74 ,abbreviations ,us$ 9 ,figures b'd4c4--basidorsal c>tilage 7neural ar*7 b'oc4--basioccipital ce4#a-d--;c5trale#a-d *4--c]atohyal clav4--clavicle clei4--clei?rum cor4--coracoid d4c4#a-d--;di/al c>pal#a-d diap4--diapophysis exoc4--exoccipital ep4--epi/]num hyo/4--hyo/apes i4--int]m$ium ,mk4--,meckel's c>tilage n4--noto*ord om4--omo/]num op4--op]culum opis4--opi/hotic p>4--p>ietal p>4 proc4--p>occipital process p]i4 c5t4--p]i*ordal c5trum p'p4--po/p>ietal prep4--prepollex pro4--prootic p'sp4--p>asph5oid pt4--pt]ygoid p4t4f4--po/-temporal fossa po/zyg4--po/zygapophysis qj4--quadratojugal qu4--quadrate ra4--radiale r4hy4--hyom&ibul> ramus ( ,,vii rib-b4--rib-be>] r4md4--m&ibul> ramus ( ,,vii sc4--scapula sc'cor4--scapulocoracoid s'd4--supradorsal c>tilage s'd47po/zyg47--supradorsal 7po/zygapophysis7 soc4--supraoccipital sp4c4--sp9al cord sq4--squamosal s'sc4--suprascapula s't4--supratemporal /a4--/apes /]4--/]num tab4--tabul> uln4--uln>e v4a4--v]tebral art]y xiph4--xiphi/]num ,i1,,iv--digits ,i & ,,iv ,v1 ,,vii1 ,x1 ,,xii--=am9a = cranial n]ves ( ^! numb]s 79 ,fig4 #d1 ,,vii is ! facial n]ve7 ,9 temnospondyl\s ,amphibia ! tympanum g5]ally occupi$ an otic not*1 at a high level on ! skull1 bord]$ dorsom$ially by ! tabul> & v5trolat]ally by ! squamosal4 ,9 ?is position ! tympanum c\ld receive airborne s\nds :e!r ! animal 7 entirely on l& or ly+ ne>ly subm]g$ ) only ! upp] "p ( its head expos$4 ,among ^? ,anura 9 :i* ! e> is n r$uc$ ! same is true1 except t ! tabul> is lo/4 ,9 ,temnospondyli 7,fig4 #c7 ! po/]ior wall ( ! otic capsule 0 usually =m$ by ! opi/hotic1 :i* ext5d$ up & outw>d z a buttress f ! exoccipital to ! tabul>1 & sometimes %[$ a p>occipital process = ! ins]tion1 presumably1 ( a slip or t5don ( ! ant]ior axial musculature4 ,! /apes1 9 addition to its foot 9 ! f5e/ra ovalis & its tympanic or extra/ap$ial process to ! tympanum1 bore a dorsal process 7or ligam5t7 to ! tabul>1 an int]nal process 7or ligam5t7 to ! quadrate or an adjac5t "p ( ! squamosal1 & a ligam5t to ! c]atohyal4 ,"s ( ^! atta*m5ts might be r$uc$ or abs5t 9 special cases1 b !y seem to h be5 ! ones orig9ally pres5t bo? phylog5etically & embryonically 9 ,amphibia4 ,among typical frogs 7,fig4 #d7 ! base1 or oto/apes1 is pres5t & bony1 ! extra/ap$ial process 7extracolumella1 or hyo/apes7 is usually c>tilag9\s1 ! dorsal process 7processus p>oticus7 is ( c>tilage or ligam5t1 b ! o!r two atta*m5ts are abs5t 9 ! adult4 ,! exoccipital ext5ds lat]ally1 occupy+ ! po/]ior face ( ! otic capsule4 ,betwe5 x & ! oto/apes is a small disc1 usually ossifi$1 ! op]culum1 :i* normally fits loosely 9 a portion ( ! f5e/ral membrane1 & is develop$ f ! otic capsule4 ,! op]cul>is muscle ext5ds f ?is disc to ! suprascapula1 9 _m b by no means all families ( ,anura4 ,illu/ration3 ,fig4 #d4 ,diagram ( middle e> /ructures 9 ,rana 7upp] figure1 aft] ,/adtmuell]1 #aicf1 & l[] left aft] ,de,beer1 #aicg71 & ,amby/oma 7l[] "r1 aft] ,de,beer1 #aicg72 all x #d4 ,= explanation ( abbreviations see ,fig4 #c4 ,among ,urodela 7,fig4 #d7 ! middle e> cavity & tympanum are lack+1 & ! /apes 7columella7 consi/s ( no m ?an its footplate & ! /ylus1 :i* is atta*$ to ! bord] ( ! squamosal1 ?us correspond+ to ! int]nal process4 ,9 families 9 :i* individuals metamorphose & become t]re/rial 7,hynobiidae1 ,amby/omidae1 ,salam&ridae1 ,ple?odontidae71 an op]culum & op]cul>is muscle appe> 9 ! adult1 j z 9 frogs1 except t 9 ,ple?odontidae1 ! mo/ progressive family1 ! op]culum fuses ) ! footplate ( ! /apes4 ,among neot5\s or p]5nibran*iate urodeles !re is no sep>ate op]culum or op]cul>is4 ,! evid5ce giv5 by ,re$ 7#aiae7 = fusion ( ! op]culum ) ! columella 9 ,necturus appe>s inconclusive1 9 spite ( ! great c>e ) :i* 8 obs]vations 7 made4 ,on ! o!r h&1 ,necturus & ,proteus alone among liv+ salam&]s h a di/9ct opi/hotic on ! po/]ior wall ( ! otic capsule 7,fig4 #c71 z d ! ,cretace\s ,hylaeobatra*us & ! ,eoc5e ,palaeoproteus4 ,probably ^! ,proteidae %\ld be reg>d$ z primitive 9 ?is respect1 al?\gh _m o!r features may be attribut$ to neot5y4 ,!re is a contra/ betwe5 ,anura & mo/ ,urodela 9 ! relative positions ( ! /apes & facial n]ve1 z %[n 9 ,de,beer's 7#aicg7 diagrams4 ,9 ! latt] 7,amby/oma7 ! n]ve is b5ea?1 & 9 ! =m] 7,rana7 above1 ! /apes4 ,judg+ by figures ( ,neoc]atodus1 ,hypogeophis1 & sev]al types ( reptiles & mammals1 ! ,urodela are exceptional4 ,necturus1 h[ev]1 has ! n]ve pass+ above its /apes1 & ?is may be primitive 9 ! same s5se z ! p]si/5t opi/hotic4 ,!re c be1 ( c\rse1 no "q ( ! n]ve hav+ work$ its way ?r\gh or ov] ! ob/ruct+ /apes 9 ord] to come bel[ x 9 salam&]s2 r1 ! p]iph]al gr[? ( neuron fib]s 9 ! embryo mu/ simply pursue a slightly diff]5t c\rse among ! p>tially diff]5tiat$ mes5*yme 9 ! two contra/+ patt]ns4 ,al?\gh ,de,beer 7#aicg7 %[s 9 8 figure ( ,hypogeophis 7"o ( ! ,apoda7 an op]culum1 ?is is app>5tly a mi/ake4 ,! /apes has a l>ge footplate1 & its /ylus articulates ) ! quadrate1 b no true op]culum or op]cul>is has be5 describ$ 9 ! ,apoda4 ,! facial n]ve passes above ! /apes4 ,x does n seem necess>y to reg>d ! conditions 9 ?is ord] z relat$ directly to ^? ( ei!r salam&]s or frogs1 b a r$uction ( ! /apes comp>able to t 9 salam&]s has occurr$4 ,! pres5ce 9 bo? frogs & t]re/rial salam&]s ( a special me*anism involv+ ! op]cul>is muscle & an op]culum cut out 9 id5tical fa%ion f ! wall ( ! otic capsule beh9d ! /apes seems to require "s o!r explanation ?an t ( a *ance conv]g5ce or p>allelism4 ,al?\gh ! /apes & otic region are readily visible 9 a numb] ( labyr9?odonts & lepospondyls1 no indication ( an op]culum seems to be report$ among !m4 ,b 9 ! ,triassic ,protobatra*us 7,fig4 #a71 :i* is unmi/akably a frog 9 its skull1 pelvis & "s o!r features1 ,piveteau 7#aicg7 has %[n1 imm$iately beh9d ! foot ( ! /apes1 a small bony tub]cle1 :i* he & ,watson 7#aidj7 designat$ opi/hotic4 ,v cle>ly x s]v$ = ins]tion ( a muscle1 & x is equally cle> t ! bone is a r$uc$ opi/hotic1 c>ry+ ! p>occipital process already m5tion$ z *>act]i/ic ( x 9 "s temnospondyls4 ,s9ce ! rema9d] ( ! po/]ior wall ( ! otic capsule consi/s ( c>tilage1 meet+ ! exoccipital1 x may be t ! opi/hotic becomes ! op]culum 9 frogs4 ,protobatra*us 0 too f> specializ$ 9 ! ,anuran direction1 al?\gh x /ill _h a tail1 & ! =elegs & h9d legs 7 ne>ly ! same size1 to be consid]$ a possible ance/or ( ! ,urodeles4 ,b at "o /age 9 ! g5]al r$uction ( ! skull 9 ! ance/ry ( bo? gr\ps1 a condition simil> to t 9 ,protobatra*us may h *>act]iz$ ! otic region1 long be=e ! ,triassic4 ,9 ! argum5t ?us f> we h consid]$ t]re/rial1 adult amphibians1 s9ce x is only 9 ^! t ei!r ! normal middle e> & tympanum1 or ! op]cul> app>atus1 is pres5t4 ,b among ! urodeles sev]al neot5ic types occur 7?is t]m applies also to ! p]5nibran*s74 ,= mo/ ( ^! !re is no?+ ab\t ! otic region t w\ld be inconsi/5t ) d]ivation1 by neot5y1 f kn[n families 9 :i* adults are t]re/rial2 = example1 ,cryptobran*us c\ld h _h a ,hynobiid-l ance/or4 ,b ?is1 z m5tion$ above1 does n hold = ! ,proteidae1 :i* possess an opi/hotic ( relatively l>ge size1 di/9ctly sep>ate f ! exoccipital & prootic4 ,ei!r ?is bone is a neomorph1 :i* seems improbable1 or !re has n be5 9 ! ance/ry ( ?is p>ticul> family an episode ( r$uction comp>able to t se5 9 ! t]re/rial families1 :]e !re is an op]culum in/ead ( a normal opi/hotic4 ,!re=e ! ,proteidae probably are n d]iv$ f ! g5]al /em ( o!r salam&]s1 b div]g$ suffici5tly long ago t ! bones ( ! otic region 7 r$uc$ on a diff]5t patt]n4 ,!y ne$ n be remov$ f ! ord]1 b1 9 ?is respect1 recogniz$ z m primitive ?an any o!r exi/+ ,urodela or ,anura4 ,a rec5t pap] by ,he*t 7#aieg7 discusses _m features ( ,necturus & ,proteus1 & %[s t !y are remote f ea* o!r2 8 evid5ce does n seem to prove1 h[ev]1 t !y 7 ( indep5d5t orig9 or t !y ne$ be plac$ 9 sep>ate families4 ,,v]tebrae ,,& ,,ribs ,developm5t ( ! v]tebrae & ribs ( ,rec5t ,amphibia has be5 /udi$ by ,gamble 7#aibb71 ,naef 7#aibi71 ,mook]jee 7#aicj a1 b71 ,gray 7#aicj7 & ,emelianov 7#aicf71 among o!rs4 ,mac,bride 7#aicb7 & ,remane 7#aich7 provide good summ>ies4 ,9 ?is section ref]5ce w be made to ! embryonic v]tebral c>tilages by ! names us$ = !m 9 ^! /udies1 al?\gh ! concept ( arcualia is curr5tly consid]$ ( little value 9 comp>ative anatomy4 ,illu/ration3 ,fig4 #e4 ,developm5t ( ,anuran v]tebrae4 ,upp] left1 late tadpole ( ,x5opus laevis2 l[] left1 same j aft] metamorphosis2 upp] "r1 diagram ( g5]al compon5ts ( primitive ,anuran v]tebra4 7,aft] ,mac,bride1 #aicb1 ,figs4 #ce1 #ch1 #dg;,d1 respectively47 ,l[] "r1 section ?r\gh ant]ior portion ( uro/yle1 imm$iately po/]ior to sacral v]tebra1 9 trans=m+ ,ascaphus truei 7orig9al1 f specim5 collect$ on ,olympic ,p59sula1 ,wa%+ton74 ,all x #bj approx4 ,= explanation ( abbreviations see ,fig4 #c4 ,! c5trum 9 ,anura 7,fig4 #e7 is =m$ 9 ! p]i*ordal %ea? 7,rana1 ,bufo7 or only 9 ! dorsal portion !re( 7,bomb9ator1 ,x5opus74 ,! neural ar* develops f ! basidorsal c>tilages t re/ ^u1 & at fir/ are entirely di/9ct f1 ! p]i*ordal %ea?4 ,ribs1 pres5t z sep>ate c>tilages associat$ ) ! #bnd1 #crd & #d? v]tebrae 9 ! l>vae ( ,x5opus & ,bomb9ator1 fuse ) lat]al processes 7diapophyses7 ( ! neural ar*es at metamorphosis1 b 9 ,leiopelma & ,ascaphus ! ribs rema9 freely articulat$ 9 ! adult4 ,basiv5tral arcualia h be5 suppos$ to be repres5t$ by ! hypo*ord1 a m$ian rod ( c>tilage b5ea? ! %r9k+ noto*ord 9 ! po/sacral region1 :i* at metamorphosis ossifies to produce ! bulk ( ! uro/yle4 ,fig4 #e1 l[] "r1 a transv]se section tak5 imm$iately po/]ior to ! sacral ribs 9 a trans=m+ specim5 ( ,ascaphus1 %[s t ! hypo*ord is a mass ( c>tilage =m$ 9 ! p]i*ordal %ea? itself1 & v obvi\sly is d]iv$ f ! v5tral "p ( po/sacral p]i*ordal c5tra2 !re are1 !n1 no basiv5tral arcualia1 & ! discrete hypo*ord %[n 9 ,mac,bride's diagram 7,fig4 #e1 upp] "r7 ( a frog v]tebra does n actually occur bel[ ! c5trum1 b only bel[ ! noto*ord 9 ! po/sacral region4 ,illu/ration3 ,fig4 #f4 ,developm5t ( ,urodele v]tebrae4 ,upp] figures1 ,triton3 at left1 l>va at #bj mm41 at "r1 diagram ( compon5ts ( v]tebra 7f ,mac,bride1 #aicb1 figs4 #ag1 #dg;,c74 ,middle figures1 ,molge vulg>is l>va3 left1 at #ah mm42 middle1 at #bj-bb mm42 "r1 at #be mm4 7f ,emelianov1 #aicf1 figs4 #cc1 #cf1 #ch respectively74 ,l[] figures1 ,necturus maculosus l>va3 left1 at #ba mm42 "r1 at #bj mm4 7f ,mac,bride1 #aicb1 figs4 #da4e1 #da4c respectively1 aft] ,gamble1 #aibb74 ,all x #bj approx4 ,= explanation ( abbreviations see ,fig4 #c4 ,9 ,urodela 7,fig4 #f7 ! patt]n ( v]tebral & rib developm5t is m complex1 & !re has be5 mu* controv]sy ov] its int]pretation4 ,neural ar*es & p]i*ordal c5tra =m 9 ! same mann] z 9 frogs1 b ) ! addition 9 c]ta9 cases 7,triton7 ( a m$ian supradorsal c>tilage1 :i* gives rise to ! zygapophyses ( ea* neural ar*4 ,difficulty comes1 h[ev]1 9 und]/&+ ! relation%ip ( ! ribs to ! v]tebrae4 ,ea* rib1 usually two-head$1 articulates ) a transv]se process t 9 its e>ly developm5t seems to be sep>ate f bo? ! v]tebra & ! rib1 & is !re=e kn[n1 noncommittally1 z rib-be>]4 ,?is lies lat]ally f ! c5trum1 neural ar*1 & v]tebral art]y2 ^u fus+ ) ! v]tebra x !re=e encloses ! art]y 9 a =am5 sep>ate f ! "o betwe5 ! capitulum & tub]culum ( ! rib 7! usual location ( ! v]tebral art]y74 ,at lea/ f\r diff]5t int]pretations ( ^! /ructures h be5 sugge/$3 7#a7 ,naef 7#aibi7 consid]$ ! rib-be>] a d]ivative ( ! basiv5tral1 :i*1 by spread+ lat]ally & dorsally to meet ! neural ar*1 enclos$ ! v]tebral art]y4 ,he !n suppos$ t by r$uction ( ! rib-be>] 9 o!r tetrapods 7frogs & amniotes7 ! v]tebr>t]ial =am5 & co/al =am5 7 br\ght toge!r 9 a s+le =am5 transv]s>ium4 ,! implication is t ! ,urodele condition is primitive1 b x _c n[ be suppos$ t ,urodela are ance/ral to any o!r gr\p1 & ! rib-be>] is mo/ probably a specialization limit$ to salam&]s4 ,?is does n1 ( c\rse1 invalidate ! fir/ "p ( 8 int]pretation4 7#b7 ,remane 7#aich71 not+ t rib ins]tions ( e>ly ,amphibia are ess5tially z 9 ,amniota1 argu$ t ! rib-be>] is n f ! basiv5tral b is a neomorph :i* orig9ates directly f ! neural ar* & gr[s v5trally4 ,?is he inf]r$ ma9ly f ,gamble's 7#aibb7 obs]vation on ,necturus1 b 8 assumption t ,necturus is m primitive ?an o!r salam&]s 7su* z ! ,salam&ridae71 :]e ! patt]n diff]s f ?is1 is n necess>ily correct4 ,r1 ! p]5nibran*s are di/+ui%$ ma9ly by _! neot5\s features1 & _! developm5t is likely to %[ simplifications :i* are n necess>ily primitive4 ,! sugge/ion ( a neomorph ought n to be made except z a la/ resort1 = x is simply an ackn[l$gm5t t ! au?or does n recognize homology ) any /ructure already kn[n2 sometimes fur!r in=mation w make su* recognition possible4 7#c7 ,gray 7#aicj71 us+ ,molge ta5iatus1 conclud$ t ! normal capitulum ( ! rib 0 lo/1 b t ! tub]culum bifurcat$ to make ! two heads se5 9 ,urodela1 ?us acc\nt+ = ! failure ( ! co/al =am5 to co9cide ) t ( ! v]tebral art]y4 ,?is answ]1 too1 seems to entail an unprovable assumption :i* %\ld n be made )\t explicit evid5ce4 7#d7 ,f9ally1 ,emelianov 7#aicf7 reg>d$ ! rib-be>] z a rudim5t>y v5tral rib1 on acc\nt ( its relation%ip to ! v]tebral art]y1 & consid]$ ! actual rib to be a neomorph 9 ! dorsal position *>act]i/ic ( tetrapod ribs 9 g5]al4 ,?is argum5t w\ld fit ! ontog5etic picture satisfactorily1 provid$ t 7a7 !re 7 "s evid5ce ( v5tral1 r ?an dorsal1 ribs 9 e>ly ,amphibia1 & 7b7 we accept ! inv5tion ( ano!r neomorph 9 mod]n ,amphibia z an unavoidable necessity4 ,emelianov's conclusion 7p4 #beh7 %\ld be quot$ "h 7translation73 ,! ribs ( ,urodela are %[n to be upp] ribs1 yet we f9d besides ^! 9 ,urodela rudim5t>y l[] ribs fus$ ) ! v]tebral column4 ,! ribs ( ,apoda are l[] ribs4 ,9 ,anura ribs fail to develop fully1 b z r>e exceptions rudim5ts ( upp] ribs appe>4 ,( ^! v>i\s int]pretations1 t ( ,naef seems to involve ! m9imum ( novelty1 namely1 t ! rib-be>] is ! basiv5tral1 exp&$ & ext]nal to ! v]tebral art]y4 ,x is n necess>y to take ?is modification z ! ance/ral condition 9 tetrapods1 ( c\rse4 ,! basiv5tral 7int]c5trum7 w\ld m]ely h exp&$ suffici5tly to provide a diapophysis = ! tub]culum z well z ! 7primitive7 facet = ! capitulum4 ,no neomorph appe>s "u ?is hypo!sis1 :i* has ! di/9ct advantage ( simplicity4 ,figures ( e>ly /ages 9 v]tebral developm5t by ! au?ors m5tion$ %[ t ! basidorsals *ondrify fir/1 z neural ar*es1 :ile a sep>ate mass ( mes5*yme lies ext]nally & v5trally f ^!4 ,?is mes5*yme may *ondrify ei!r 9 "o piece 7on ea* side7 or 9 two2 9 ,molge ! "p adjac5t to ! c5trum is ossifi$ 9 ! #bj-mm4 l>va1 & subsequ5tly unites ) ! m dorsal & lat]al c>tilag9\s "p1 :ile ! rib1 appe>+ f>!r out1 gr[s inw>d to meet ?is composite rib-be>]4 ,9 ,necturus ! mes5*yme bel[ ! neural ar* diff]5tiates into a c>tilage bel[ ! v]tebral art]y 7position prop] to a basiv5tral71 a bridge betwe5 ?is & ! neural ar*1 & a rib1 ! latt] two *ondrify+ lat] ?an ! basiv5tral prop]4 ,9 ! axolotl 7presumably ,amby/oma tigr9um7 ! rib-be>] gr[s d[nw>d f its fir/ c5t] ( *ondrification at ! side ( ! neural ar* 7,emelianov1 #aicf74 ,?us x appe>s t ! simple/ hypo!sis to acc\nt = ! rib-be>] is t 7a7 x is ! basiv5tral1 7b7 x is recognizable j be=e *ondrification z a mass ( mes5*yme 9 contact ) bo? ! noto*ordal %ea? & ! basidorsal c>tilage1 7c7 x may *ondrify or ossify fir/ 9 its v5tral portion or 9 its dorsal portion1 ! two !n jo9+ be=e x fuses ) ! re/ ( ! v]tebra1 7d7 ! enclosure ( ! v]tebral art]y is a consequ5ce ( ! ext5sion ( ! basiv5tral beyond ! position occupi$ by x 9 primitive ,amphibia1 & 7e7 !re is no indication t ?is took place 9 o!r ord]s ?an ! ,urodela4 ,x seems t ! v]tebrae 9 ,urodela h at lea/ ! foll[+ compon5ts3 p]i*ordal c5tra1 sep>ate basidorsal c>tilages1 & basiv5trals1 :i* are some:at specializ$ 9 _! mann] ( developm5t4 ,! v]tebrae ( ,anura develop 9 ! fa%ion j describ$ except t basiv5trals are lack+4 ,x w\ld seem no m difficult to accept ! d]ivation ( salam&] v]tebrae f ! temnospondyl\s type ?an x is 9 ! case ( frogs1 if o!r evid5ce po9ts to su* an ance/ry4 ,illu/ration3 ,fig4 #g4 ,v]tebrae ( ,eu/h5opt]on 7x#a7 & ,i*?yo/ega 7x#b_/c1 aft] ,j>vik1 #aieb71 ,trim]orha*is 7x#a-a_/b1 aft] ,case71 & ,amphibamus 7x#aj1 aft] ,watson1 #aidj7 9 lat]al & end views2 ! two l[] "r-h& figures are f ,watson 7#aidj1 z ,miobatra*us72 ! l[] left is f a ca/ ( ! ,miobatra*us specim5 9 ,*icago ,natural ,hi/ory ,museum1 ,no4 #bjjj1 9 ! presacral region 7orig9al1 x#aj74 ,fig4 #g1 l[] "r1 is ,watson's 7#aidj7 illu/ration ( ! ant]ior trunk v]tebrae ( ,amphibamus 7,miobatra*us71 9 :i* ! int]c5trum is %[n z a s+le m$ian piece4 ,fig4 #g1 l[] left1 %[s two ( ! m po/]ior trunk v]tebrae se5 z impressions 9 a ca/ ( ! type ( ,miobatra*us rom]i2 evid5tly ! int]-c5tra 7 pair$ at ab\t ! level ( ! #af? v]tebra1 & relatively l>ge4 ,gregory's 7#aiej7 figure ( ! type specim5 ( ,mazon]peton 7also equival5t to ,amphibamus7 %[s ! ant]ior trunk v]tebrae 9 relation to ! ribs ess5tially z !y appe> to me 9 ! ca/ ( ,miobatra*us1 & r diff]5tly f ,watson's figure ( ! latt]4 ,gregory is probably "r 9 consid]+ ! specim5s to repres5t v>i\s degrees ( immaturity4 ,s f> z pres5t in=mation goes1 !n1 ! v]tebrae ( salam&]s & frogs %[ no cle> evid5ce ( d]ivation f ^? ( any p>ticul> gr\p among ! e>ly ,amphibia1 b _! features are n inconsi/5t ) a simplification ( ! patt]n ( ,temnospondyli4 ,illu/ration3 ,fig4 #h4 ,pectoral girdles ( ,protobatra*us 7aft] ,piveteau1 #aicg71 ,notobatra*us 7aft] ,/ipanicic & ,reig1 #aief71 ,ascaphus 7aft] ,ritl&1 #aiee a7 & ,rana 7orig9al72 all x#b4 ,= explanation ( abbreviations see ,fig4 #c4 ,,pectoral ,,girdle ,he*t & ,ruibal 7,copeia1 #aibh3bdb7 make a /rong po9t ( ! nature ( ! pectoral girdle 9 ,notobatra*us1 z describ$ rec5tly by ,/ipanicic & ,reig 7#aiee1 #aief7 f ! ,jurassic ( ,patagonia1 & q rightly recomm5d t ! significance ( ! arcif]al & firmi/]nal types ( girdle be re/udi$4 ,t ( ,notobatra*us is said to be firmi/]nal2 9 view ( ! arcif]al condition 9 ! suppos$ly primitive ,leiopelma1 ,ascaphus1 ,bomb9ator1 etc41 ?is comes z a surprise4 ,is ! firmi/]nal girdle1 z se5 9 ,rana1 ,bufo1 & o!rs1 actually ! ance/ral type1 & has ! arcif]al be5 d]iv$ f some?+ l ?is8 ,9 ! figures giv5 by ,/ipanicic & ,reig ! ossifi$ p>ts ( ! girdle are figur$ 9 detail 7,fig4 #h7 & ,reig's discussion ( x is ?or\gh4 ,! decision to call x firmi/]nal 0 tak5 ) "s hesitancy1 = no m$ian elem5ts are indicat$1 & ! position & %ape ( ^? se5 is closely simil> to ! ossifi$ p>ts 9 ,ascaphus & ,leiopelma2 !re is no bony /]num or omo/]num4 ,x is safe to suppose t "s c>tilage lay 9 ! midl9e betwe5 ! clavicles & coracoids1 b !re is no evid5ce z to its ext5t1 rigidity1 or degree ( ov]lapp+ if any4 ,app>5tly1 !n1 !re is n suffici5t reason to inf] t ?is ,jurassic frog _h a pectoral girdle comp>able ) ! mod]n firmi/]nal type4 ,piveteau 7#aiee3bfa7 rem>ks t ! only liv+ ,anuran t c be comp>$ usefully ) ,protobatra*us 7,triassic7 ) reg>d to its pectoral girdle is ,ascaphus4 ,aga91 ! ext5t ( c>tilage 9 ,protobatra*us 7,fig4 #h7 c only be inf]r$1 & !re are no m$ian elem5ts4 ,! agreem5t ) ,ascaphus includes ! pres5ce1 9 bo?1 ( a sep>ate coracoid ossification situat$ po/]ior to ! ossifi$ scapulocoracoid 7actually scapula74 ,?is ossification is evid5tly t %[n 9 ,notobatra*us z coracoid4 ,direct comp>ison ( ! ?ree g5]a ) "o ano!r sugge/s t if we use ! t]m arcif]al = any1 we %\ld use x = all4 ,9 ! remote pr$ecessor ( ,anura1 ,amphibamus ( ! ,p5nsylvanian1 ! pectoral girdle 0 less sub/antial ?an 9 _m ( its contempor>ies1 b x conta9$ ! primitive m$ian int]clavicle 9 addition to ! clavicle1 clei?rum1 & scapulocoracoid4 7,! figure ( ,watson1 #aidj1 & t by ,gregory1 #aiej1 are ( individuals ( diff]5t ages1 ! latt] be+ old]47 ,x is cle> t ! pair$ elem5ts ( su* a girdle 7 held rigid by _! atta*m5t to ! int]clavicle1 via ! clavicles4 ,subsequ5t elim9ation ( ! int]clavicle 9 ! ,anuran l9e ( desc5t1 & decrease ( ossification1 left a girdle l t ( ,protobatra*us1 ,notobatra*us1 ,ascaphus & ,leiopelma4 ,b 9 sev]al advanc$ families a m rigid m$ian /]num1 ( "o or two bony pieces plus c>tilage1 is develop$ second>ily1 possibly 7z ,cope1 #ahhi3 #bdg1 sugge/$7 9 correlation ) axill>y amplexus4 ,among ,urodela no d]mal bones occur 9 ! pectoral girdle4 ,!re is usually a scapulocoracoid ossifi$ z a s+le piece1 f :i* a ?9 c>tilag9\s suprascapula ext5ds dorsally & a broad c>tilag9\s coracoid plate ext5ds m$ially1 ov]lapp+ ! "o f ! opposite side2 a precoracoid lobe ( ?is rea*es =w>d on ei!r side1 & a m$ian1 po/]ior /]num ( c>tilage may make contact ) ! edges ( ! two coracoids4 ,9 ,sir5 & ,amphiuma two c5t]s ( ossification are f\nd = ea* scapulocoracoid1 & 9 ,triton & ,salam&ra ?ree4 ,probably ! m dorsal & lat]al ( ^! repres5ts ! primitive scapula & ! o!r "o 7or two7 ! primitive coracoid4 ,comp>+ ! girdle ( a salam&] ) t ( a frog1 ! close/ simil>ity c be se5 betwe5 ,ascaphus & a salam&] 9 :i* ! scapula & coracoid ossify sep>ately4 ,bo? h ! m$ian /]num 9 contact ) ! coracoid plates4 ,! major diff]5ce1 ( c\rse1 is ! lack ( clavicle & clei?rum 9 ! salam&]4 ,,c>pus ,,& ,,t>sus ,9 ,ascaphus 7,ritl&1 #aiee;a2 cle>$ & /a9$ specim5s ( ne>ly gr[n males7 di/al c>pals #a1 #b1 #c & #d are pres5t & sep>ate1 increas+ 9 size 9 ! ord] giv5 7,fig4 #i74 ,a prepollex re/s aga9/ c5trale #a2 c5tralia #b & #c are fus$2 ! radiale fuses ) c5trale #d1 & ! int]m$ium fuses ) ! uln>e2 radius & ulna are fus$ ) ea* o!r z 9 o!r frogs4 ,! digits 7& metac>pals7 are consid]$ by ,ritl& to be #a-d1 9 addition to ! prepollex1 r ?an #b-e4 ,illu/ration3 ,fig4 #i4 ,skeleton ( =e foot ( ,notobatra*us 7aft] ,/ipanicic & ,reig1 #aief1 t]m9ology revis$7 & ,ascaphus 7aft] ,ritl&1 #aiee a72 all x#e4 ,= explanation ( abbreviations see ,fig4 #c4 ,9 ! ,jurassic ,notobatra*us ,/ipanicic & ,reig 7#aief7 h %[n ! c>pus ) surpris+ cl>ity 7,fig4 #i74 ,if _! nom5clature ( ! p>ts be revis$1 we obta9 a fairly close resemblance to ,ascaphus1 except t c5tralia #b & #c are n fus$1 di/al c>pals #a & #b d n %[ 7:i* w\ld easily be und]/ood if !y 7 ( ! size ( ^? 9 ,ascaphus1 or n ossifi$71 & ! int]m$ium rema9s sep>ate f ! uln>e4 ,9 ,salam&ra 7,francis1 #aicd2 ,nauck1 #aich7 di/al c>pals #a & #b are fus$ 9 bo? l>va & adult1 & #c & #d are sep>ate2 ! radiale1 int]m$ium & uln>e are sep>ate 9 ! l>va b ! latt] two fuse 9 ! adult2 c5trale #a 7labell$ prepollical c>tilage by ,francis7 & c5trale #b are sep>ate4 ,francis consid]s ! digits 7& metac>pals7 to be #a-d4 ,app>5tly ! arrangem5t "h indicat$ = ! l>va is *>act]i/ic ( o!r l>val salam&]s1 except :]e fur!r r$uc$1 & r$uction bel[ ! numb] giv5 = ! adult is common 9 o!r t]re/rial =ms4 ,! radius & ulna are1 ( c\rse1 sep>ate4 ,! ossification ( c>pals is m likely to be complete 9 adult frogs ?an 9 salam&]s1 b "s ossification ( all p>ts nam$ is f\nd 9 sev]al ( ! latt]4 ,a common ance/or ( frogs & salam&]s c\ld be expect$ to h ! foll[+ elem5ts pres5t & ossifi$ 9 ! adult3 di/al c>pals #a-d sep>ate2 #c c5tralia2 radiale1 int]m$ium & uln>e sep>ate4 ,comp>ison ) fossils old] ?an ,notobatra*us is fruitless on ^! po9ts1 unless we g back to =ms too di/ant to h any special value1 su* z ,eryops4 ,?is is because ( inadequate pres]vation & because ! elem5ts are n fully ossifi$ 9 _m immature specim5s4 ,= ! purpose ( ?is review !re is no special value 9 a comp>ison ( ! t>si ( frogs & salam&]s1 s9ce ! leap+ adaptation ( ! =m] leaves v little common patt]n betwe5 !m4 ,ev5 9 ,protobatra*us1 :]e ! legs 7 n yet conspicu\sly l5g!n$1 ! tibiale & fibul>e 7a/ragalus & calcaneum respectively7 7 already consid]ably elongat$4 ,! c>pus & t>sus ( ,amphibamus are z yet undeciph]able4 ,,! ,,l>va ,consid]+ ! po/embryonic developm5tal /ages ( mod]n ,amphibia1 !re c be no d\bt t a gill-be>+1 f\r-legg$ l>va ( a salam&]1 9 :i* lat]al l9e pores & a gul> fold are pres5t1 repres5ts mu* m closely ! type ( l>va f\nd 9 labyr9?odonts ?an does ! limbless1 plant-nibbl+ tadpole ( ! ,anura4 ,salam&]-l l>vae ( labyr9?odonts are well kn[n1 especially ^? =m]ly suppos$ to comprise ! ord] ,bran*iosauria4 ,_m1 p]haps ! majority (1 labyr9?odonts %[ "s features associat$ ) aquatic life ev5 :5 full-gr[n1 z d ! lepospondyls4 ,^! features may include impressions ( s5sory canals on ! d]mal bones ( ! skull1 p]si/5ce ( visc]al ar*es1 r$uction 9 size ( app5dages1 & failure ( t>sal & c>pal elem5ts to ossify4 ,9 fact1 x appe>s t v few ( ! ,paleozoic ,amphibia 7 successful 9 e/abli%+ !mselves z t]re/rial animals ev5 z adults4 ,nev]!less1 9 ! ance/ry ( ,anura1 & t ( at lea/ ! ,hynobiid1 ,amby/omid1 ,salam&rid & ,ple?odontid salam&]s1 !re mu/ c]ta9ly h be5 a t]re/rial adult1 trans=m+ f an aquatic l>va4 ,! leap+ me*anism ( ,anura1 %[n 9 s _m features ( _! anatomy1 is p]haps to be expla9$ z a device = sudd5 escape f l& into ! wat]1 b x 0 n yet p]fect$ 9 ! ,triassic ,protobatra*us or ! ,jurassic ,notobatra*us4 ,! middle e>1 its s\nd-transmitt+ me*anism1 & ! tympanum1 well develop$ 9 mo/ ,anura1 are readily d]iv$ f ^? ( e>ly labyr9?odonts1 & are presumably effective = he>+ airborne s\nds :e!r on l& or :ile float+ 9 ! wat]4 ,r$uction ( ^! organs 9 ,urodela may be correlat$ ) _! cu/om>y re/riction to subsurface habitats & inability to ma9ta9 a float+ position :ile 9 wat]4 ,"s light may be %$ on ! significance ( ! tadpole ( ,anura by consid]+ ! e>ly /ages ( ! ribb$ frogs1 ,liopelmidae4 ,leiopelma & ,ascaphus are s closely simil> 9 ! adult t !re is no d\bt t !y belong 9 "o family1 primitive 9 "s respects 7includ+ articulat$ ribs2 pyri=mis & caudalipubois*iotibialis muscles7 b n 9 o!rs 7abs5ce ( tympanum & middle e>74 ,9 bo? g5]a ! eggs are l>ge1 #e mm4 9 ,leiopelma1 #d4e mm4 9 ,ascaphus1 & unpigm5t$2 b at ?is po9t ! resemblance ends4 ,illu/ration3 ,fig4 #aj4 ,leiopelma ho*/ett]i l>va1 lat]al & v5tral 7aft] ,/eph5son1 #aiee71 x#d4 ,/eph5son 7#aiee7 %[$ t embryos ( ,l4 ho*/ett]i develop equally well on l& 79 damp places7 or 9 ! wat]1 & t embryos prematurely releas$ f egg capsules develop successfully 9 ! wat]4 ,! l>vae possess bo? pairs ( legs 7,fig4 #aj7 & a broad gul> fold simil> to t ( l>val salam&]s4 ,9 ,l4 ho*/ett]i ! fold gr[s back ov] ! =elegs tempor>ily1 b rema9s free f ! body & pres5tly ! legs reappe>1 :]eas 9 ,l4 ar*eyi ! =elegs are n cov]$ at any "t4 ,no bran*ial *amb] or spiracle is =m$4 ,( c\rse direct developm5t1 )\t a tadpole1 occurs 9 sev]al o!r gr\ps ( ,anura1 b 9 ea* case t]re/rial adaptations are obvi\s4 ,?is is n true ( ,leiopelma1 :i* ,/eph5son reg>ds z m ne>ly comp>able ) ,urodela 9 its developm5t ?an ) o!r ,anura1 & he sees 9 x a prim>y & amphibi\s mode in/ead ( a t]re/rial specialization4 ,! ,ascaphus tadpole be>s no outw>d resemblance to ! l>va ( ,leiopelma1 b is a normal tadpole 9 =m1 al?\gh sluggi% 9 activity4 ,its greatly exp&$ labial folds be> num]\s r[s ( horny epid]mal tee?1 :i*1 ) ! lips1 s]ve to an*or ! tadpole to /ones 9 ! swift wat] ( m\nta9 brooks4 ,noble 7#aibg7 notic$ t p>ticles ( food 7 tak5 9 ?r\gh ! ext]nal n>es1 & t a curr5t ( wat] pass$ ?r\gh ^! op5+s & out by way ( ! m$ian spiracle4 ,x appe>s t any action by ! tee? & jaws 9 scrap+ algae f ! rocks 7:i* 7 b>e 9 ! /ream :]e ,i h collect$ ,ascaphus7 w\ld be q incid5tal1 & t ! lips & tee? mu/ be prim>ily a cl++ me*anism4 ,c]ta9 o!r m\nta9 brook tadpoles 7= example1 ,borborocoetes7 %[ simil> devices1 b ^! are develop$ indep5d5tly1 z specializations f ! usual sort ( tadpole4 ,may x n be t closure ( ! gill-*amb] by ! op]cul> 7gul>7 fold1 ret>dation ( limb developm5t1 expansion ( ! lips1 gr[? ( p>allel r[s ( horny tee?1 & o!r correlat$ features t make a tadpole1 7 br\ght ab\t z an adaptation ( ! primitive ,anuran l>va to a swift-/ream habitat1 & t ?is basic pat5t !n lat] s]v$ to admit ! tadpoles ( desc5dant types to an alga-scrap+ habit 9 quiet wat] z well8 ,! tadpole1 z a unique l>val type among v]tebrates1 be>s ! hallm>ks ( an abrupt adaptive %ift1 su* z might h occurr$ )9 ! limits ( a s+le family1 & x seems difficult to imag9e ! enclos$ bran*ial *amb]1 ! too?-r[s1 & lips ( a famili> tadpole z hav+ evolv$ )\t "s k9d ( suctorial function along ! way4 ,,summ>y ,! ,anura probably orig9at$ among temnospondyl\s labyr9?odonts1 ?r\gh a l9e repres5t$ approximately by ,eugyr9us1 ,amphibamus1 & ! ,triassic frog ,protobatra*us1 z %[n by ,watson1 ,piveteau & o!rs4 ,! kn[n ,paleozoic lepospondyls d n %[ cle> indications ( a relation%ip ) ,urodela1 b ,lysorophus may well be on ! ance/ral /em ( ! ,apoda4 ,betwe5 ,urodela & ,anura !re are num]\s resemblances :i* seem to indicate direct relation%ip ?r\gh a common /ock3 7#a7 a simil> r$uction ( d]mal bones ( ! skull & expansion ( palatal vacuities2 7#b7 movable basipt]ygoid articulation 9 primitive memb]s ( bo? ord]s2 7#c7 an op]culum =m$ 9 ! otic capsule1 ) op]cul>is muscle2 7#d7 _m details ( cranial developm5t1 cranial muscles1 & ?igh muscles1 especially betwe5 ,ascaphus & ! ,urodela1 z %[n by ,pusey & ,noble2 7#e7 ess5tially simil> mann] ( v]tebral developm5t1 q consi/5t ) d]ivation ( bo? ord]s f ,temnospondyli2 7#f7 pres5ce 9 ! l>va ( ,leiopelma ( a salam&]-l gul> fold1 f\r limbs1 & no sugge/ion ( modification f a tadpole 7,/eph5son74 ,,lit]ature ,,cit$ ,broom1 ,r4 #aiah4 ,obs]vations on ! g5us ,lysorophus ,cope4 ,ann4 ,mag4 ,nat4 ,hi/41 7#i7b3bcb-bci4 ,by/r[1 ,a4 ,p4 #aich4 ,dv9osaurus als neot5is*e ,=m d] ,/egocephal54 ,acta ,zool41 #ai3bji-bie4 ,case1 ,e4 ,c4 #aice4 ,description ( a collection ( associat$ skeletons ( ,trim]orha*is4 ,contrib4 ,mus4 ,pal4 ,univ4 ,mi*igan1 #d3bbg-bgd4 ,cope1 ,e4 ,d4 #ahhi4 ,! ,batra*ia ( ,nor? ,am]ica4 ,bull4 ,u4 ,s4 ,nat4 ,mus41 #cd3a-ebe4 de ,be]1 ,g4 ,r4 #aicg4 ,! developm5t ( ! v]tebrate skull4 ,pp4 xxiii #eeb4 ,ox=d1 ,cl>5don ,press4 de ,villi]s1 ,c4 ,g4 ,s4 #aicd4 ,/udies ( ! cranial anatomy ( ,ascaphus truei ,/ejneg]1 ! ,am]ican ,liopelmid4 ,bull4 ,mus4 ,comp4 ,zool41 #gg3a-ch4 ,emelianov1 ,s4 ,w4 #aicf4 ,die ,morphologie d] ,tetrapod5ripp54 ,zool4 ,jahrb4 7,anat471 #fb3agc-bgd4 ,francis1 ,e4 ,t4 ,b4 #aicd4 ,! anatomy ( ! salam&]4 ,pp4 xxxi #cha4 ,ox=d1 ,cl>5don ,press4 ,gamble1 ,d4 ,l4 #aibb4 ,! morphology ( ! ribs & ! transv]se processes ( ,necturus maculatus4 ,j\r4 ,morph41 #cf3ecg-eff4 ,gray1 ,p4 #aicj4 ,on ! atta*m5ts ( ! ,urodele rib to ! v]tebra & _! homologies ) ! capitulum & tub]culum ( ! ,amniote rib4 ,proc4 ,zool4 ,soc4 ,london1 #aicj7aica73ijg-iaa4 ,gregory1 ,j4 ,t4 #aiej4 ,tetrapods f ! ,p5nsylvanian nodules f ,mazon ,creek1 ,ill9ois4 ,am4 ,j\r4 ,sci41 #bdh3hcc-hgc4 ,he*t1 ,m4 ,e4 #aieg4 ,a case ( p>allel evolution 9 salam&]s4 ,proc4 ,zool4 ,soc4 ,calcutta1 ,mook]jee ,mem43#bhc-bib4 ,holmgr51 ,n4 #aicc4 ,on ! orig9 ( ! tetrapod limb4 ,acta ,zool41 #ad3ahe-bie4 #aici4 ,contributions to ! "q ( ! orig9 ( ! tetrapod limb4 ,acta ,zool41 #bj3hi-abd4 #aidi;a4 ,contributions to ! "q ( ! orig9 ( tetrapods4 ,acta ,zool41 #cj3dei-dhd4 #aidi;b4 ,on ! tetrapod limb problem aga94 ,acta ,zool41 #cj3dhe-ejh4 ,h]re1 ,w4 #aice4 ,die ,s*wanzlur*e d] mitteleoca55 7ob]lutetis*57 ,braunkohle des ,geiseltales und die ,phylog5ie d] ,urodel5 unt] ,e9s*luss d] fossil5 ,=m54 ,zoologica1 #cc3hg1 #a-e4 ,j>vik1 ,e4 #aidb4 ,on ! /ructure ( ! sn\t ( ,crossopt]ygians & l[] gna?o/omes 9 g5]al4 ,zool4 ,bidrag fran ,upsala1 #ba3bce-fge4 #aieb4 ,on ! fi%-l tail 9 ! ,i*?yo/egid ,/egocephalians4 ,m$delels] on ,gronl&1 #aad7ab73a-ij4 ,mook]jee1 ,h4,k4 #aicj;a4 ,on ! developm5t ( ! v]tebral column ( ! ,urodela4 ,phil4 ,trans4 ,roy4 ,soc4 ,london1 ,b #bah3dae-ddf4 #aicj;b4 ,on ! developm5t ( ! v]tebral column ( ! ,anura4 ,philos4 ,trans4 ,royal ,soc4 ,london1 ,b #bai3afe-aif4 ,mac,bride1 ,e4,w4 #aicb4 ,rec5t "w on ! developm5t ( ! v]tebral column4 ,cambridge1 ,biol4 ,rev41 #g3ajh-adh4 ,mc,dowell1 ,s4,b4 #aieh4 ,are ! frogs specializ$ seym\riamorphs8 7,ab/ract7 ,anat4 ,rec41 #acb7c73dgb4 ,naef1 ,a4 #aibi4 ,notiz5 zur ,morphologie und ,/ammesges*i*te d] ,wirbelti]e4 #ae4 ,dreissig ,!s5 ueb] ,wirbelsaeule und ,ripp51 insbesond]e bei d5 ,tetrapod54 ,zool4 ,jahrb41 #ej3eha-fjj4 ,noble1 ,g4 ,k4 #aibb4 ,! phylog5y ( ! ,sali5tia2 ,i4 ,! o/eology & ! ?igh musculature2 _! be>+ on classification & phylog5y4 ,bull4 ,am]4 ,mus4 ,nat4 ,hi/41 #df3a-hg4 #aibg4 ,! value ( life-hi/ory data 9 ! /udy ( ! evolution ( ! ,amphibia4 ,annals ,new ,york ,acad4 ,sci41 #cj3ca-abh4 ,piveteau1 ,j4 #aicg4 ,un ,amphibi5 du ,trias inf]ieur4 ,essai sur l'orig9e et l'evolution des ,amphibi5s ,an\res4 ,annales de ,paleontologie1 #bf3ace-agf4 #aiee4 ,an\ra4 ,93 ,traite de ,paleontologie1 #e3bej-bgd4 ,j4 ,piveteau1 ,masson et ,cie1 ,p>is4 ,pusey1 ,h4 ,k4 #aidc4 ,on ! head ( ! liopelmid frog1 ,ascaphus truei4 ,i4 ,! *ondrocranium1 jaws1 ar*es1 & muscles ( a p>tly gr[n l>va4 ,qu>t4 ,j\r4 ,micr4 ,sci41 #hd3aje-ahe4 ,re$1 ,h4 ,d4 #aiae4 ,! s\nd-transmitt+ app>atus 9 ,necturus4 ,anat4 ,rec41 #i3eha-eij4 ,remane1 ,a4 #aicf4 ,wirbelsaeule und ihre ,abkoemml+e4 ,93 ,h&bu* d] v]glei*5d5 ,anatomie d] ,wirbelti]e1 ,l4 ,bolk et al41 #d3a-bjf4 ,urban & ,s*w>z5b]g1 ,b]l91 ,vi5na4 ,ritl&1 ,r4 ,m4 #aiee;a4 ,/udies on ! po/-cranial morphology ( ,ascaphus truei4 ,i4 ,skeleton & sp9al n]ves4 ,j\r4 ,morph41 #ig3aai-agd4 #aiee;b4 ,/udies on ! po/-cranial morphology ( ,ascaphus truei4 ,,ii4 ,myology4 ,j\r4 ,morph41 #ig3bae-bhb4 ,rom]1 ,a4 ,s4 #aide4 ,v]tebrate paleontology4 #bnd edition4 ,pp4 viii #fhg4 ,univ4 ,*icago ,press4 #aidg4 ,review ( ! ,labyr9?odontia4 ,bull4 ,mus4 ,comp4 ,zool41 #ii3c-cfh4 ,saeve-,so$]b]gh1 ,g4 #aicd4 ,"s po9ts ( view conc]n+ ! evolution ( ! v]tebrates & ! classification ( ?is gr\p4 ,arkiv fo] ,zoologi1 #bf;,a3#a-bj4 ,/adtmuell]1 ,f4 #aicf4 ,kranium und ,visc]alskelett d] ,/egocephal5 und ,amphibi54 ,93 ,h&bu* d] v]glei*5d5 ,anatomie d] ,wirbelti]e1 by ,l4 ,bolk et al41 #d3eja-fih4 ,/eph5son1 ,n4 ,g4 #aiee4 ,on ! developm5t ( ! frog1 ,leiopelma ho*/ett]i ,fitz+]4 ,proc4 ,zool4 ,soc4 ,london1 #abd7d73ghe-gie4 ,/ipanicic1 ,p4 ,n4 & ,reig1 ,o4 ,a4 #aiee4 ,breve noticia sobre el hallazgo de anuros en el d5om9ado ,complejo ,porfirico de la ,patagonia ,extra&9a1 con consid]aciones ac]ca de la composicion geologica del mismo4 ,revi/a de la ,asoc4 ,geol4 ,arg5t9a1 #aj7d73bae-bcc4 #aief4 ,el complejo porfirico de la ,patagonia extra&9a y su fauna de ,anuros4 ,acta ,geol4 ,lilloana 7,univ4 ,nac4 del ,tucuman71 #a3ahe-big4 ,su%k91 ,p4 ,p4 #aicf4 ,notes on ! pro-,jurassic ,tetrapoda f ,u4 ,s4 ,s4 ,r4 ,,iii4 ,dv9osaurus ,amalitzky1 a p]5nibran*iate /egocephalian f ! ,upp] ,p]mian ( ,nor? ,dv9a4 ,trav4 ,in/4 ,pal4 ,acad4 ,sci4 ,,urss1 #e3dc-ia4 ,watson1 ,d4 ,m4 ,s4 #aidj4 ,! orig9 ( frogs4 ,trans4 ,roy4 ,soc4 ,ed9burgh1 #dj7g73aie-bca4 ,transmitt$ ,april #g1 #aiei4