30 



miLl.KTIN :il, I'MIKI* STATKN NAIIoNAh MISKUM. 





The most priiiiitivf roiiii of tlic cxisliiij,' CnMh'lii is !i|ti»;ir('iitl.v Ciyp- 

 |()l)i'aii>'liiis. 



\Vit'(l( tsIk ill) ' (/. <:, p. !>.■») Ims iitti'iniiU'd to tnici; tin* aiuH'stry of llio 

 ("n'ciliidii- to the St(';,n)i!i'itliiili of the (-'.iil»:)iiilV'r()iis pi'iiod, from \vlii(;li 

 Iio supposes tln'iii to liiivf arisen by a process of (IcjfciiciMtioii. lie re- 

 marks that ill order to (h'liioiistiafe this piopDsitioa if is only necessary 

 to discover a type witli rudimeiital iimlH wliichsiiali coiii!ecf the two. 



Th.it the Ca-ci iida' is a type which lias resulted from a (Iciiciieratioii, 

 I have also proposed,! Imt I have derived liiem from the t'rodela rather 

 than from tiie Stef;oeepl;ali direct. They have, lii<e Amphiiiiiia, essen 

 tiallylliesaaiecraiiial structure as tlie L'roilela, wh'w.h is widely dilVereiit 

 from tiiat of the Stc;,'()cepliali, in tlie absence of the intercalare, supra 

 temporal, basioccipit il and pnstorbital b mics. And these cliiiracter.s 

 are fully Miaiiitained in various <;enera ol' Ste;;dcepliali wiiich have I'udi 

 mciita' liadis. Amjdnnma then is the annectant type with iiidinicntal 

 limbs \liich Dr. Wiedersheim s(»n<;lit for. The cir(!iiiiistaiice that his 

 eyes weie turned toward the Hteyocephali iiidisp(»sed liim to recognize 

 this fact. 



Tlicalliiiitiesof the re(;cnt families, which may be re.narded as phylo 

 genetic, may be reiircsented as follows: 



Circiliiilii'. 



I 

 Anipliiiiiiii(hi'. 



' I'lcllllMUIillM'. 



Ilcsiiio^iialliid,!'. 



I'iftliulmiti.hc. Salam.oidiida'. 



Aiiililvstdiiiiihi'. 



'J'lioriiili ' 



\ 



t'i;v|iti)l)raiiflii(l:i 



i 



cuYrTor.iiANciiiDj:. 



Vertebra' aiiipliico'lous, without anterior double Iivpopophysis Tail 

 deveh.ped. Parietal and prefrontal bones embracing froi.tals, ami 

 n.eefing above orbits. Vestibule with internal wall membranous. No 

 ethmoid bone. Carpus and tarsus cartilaginous. Voineropalatine teeth 

 on anterior border of bone of that name. Pterygoi<l bone present. 

 •Auutoiuie der Gymuoi-Uioucu, Jcua, 167'J. tAm.ricau Naturalist, iSSo, p. '^4.1. 



