$0 & -jl 



> g OF Clltg g 



7. The yft ; ;honb 



Structure 



Page 

 105 



The prechordal porti on of the chondrucraniutn of fefifc "adult 

 Chhmera is di i r rj^rh^rrin tro a n trrhtriy ^ it n d not anterior^ aa 

 Hubree I it-'s ( l^fT j » I 



This is '-V y b 



hi I ' 



O 



6 



ol", ms m the Selaehii, laU&f gradually acquiring 1 * 

 approximately in the line p\»Wttged of fcheparacboi • 

 ehondiwcranimn of Ghimcera 1 at these early stages has l 

 tunattfcf »qt been described. ISSyis, howev%r> bejn de 

 certain of<jfche £ el ichii, <jk,nd ai sligLtb 



th> 

 ribing thobe 



these sta. 

 in Gallor/blpt^tfMSj 

 in these embryos c 

 adult Chimcertt. 



i*3 reference 



thes 



i fishes 



LYiust 3e m; 

 bef or j^cl 



fin. 



St) 



and :p J^, 4 -< *_d lr«uee Qroba^ly in al^,ol 



m 



In $cantit->a? and 

 Selachii, the cramai>j > sT' "V 



wertzoflf's (18f9ffigi 

 ol* embryos oi these fishes, the parachordals and the end 

 notoehord project sligptly into fciie hollow of the mesocephali 

 flexure (plica encepblli ven trims Avon Kupffer, 1906). 

 trabecule jiannot, apcording\y,v be /laid dowrv in the line 



longed of 



Us p.a.ra.cJ 



pre 



lormal relations 

 t lie at right 



to the ventral surface of theMajj^*!; they at 

 angles to j^ iu paiwchuL ' dals gnd slightly posterior toYtheir 

 ends. The marked cranial flexure at this stage alio affect h 

 position of f - all (mo v is ceral j g^clieg tlf?6W lie an 

 arch, andrth© pLlatoquadr&te and mandibnhi. I 



cartilaginous bar of the nuaidibuW /- of 

 mc with patfts of fche"4nrsof etiGjfor more pre- 

 \\i-> laid (jbwa, at «ght angles to 



+ 1. 



£0 



wrhei 

 ton e 



917, 



nea 



II, 



horizontal! ins to 



see p. 



