ON 'I'lIK Foi: TAL M EM IJüAXKS Ol' CllELONTA. !'• 



II. Origin of the Allanlois. 



lu'siilcs KitpH'rr who (U'i'ivcs tlu- allantois tVoiii iho lU'inviitoric 

 onnal. the one wlio has most can-l'iilly studied its origin in Kcjiiilia 

 is Strahl (Xos. 1 and 2). Acc(n'dinp; in this anth»n'. tlie allantois is 

 laid, in Fvaccrta, as a solid knol) at the post<'rior end of the emhrvo, 

 suhsequentlv hollows itself out, and only then comes to eonnniinicate 

 with the hind-gut hy an independcMitly formed allantoie stalk. Ft 

 then tiu'ns rciiind the tail end and comes to lie in lV<Mit of. anil lielow, 

 the latter. 



After Strahl, llotl'niann (Xos. (! and 7) and I'ereiiyi (Xo. l(i) 

 have studied the oi"igin of the alhintois in lve])tiria. The \ lews 

 whieh Holfmaim expresses in his lirst papei- (Xo. (5) mainly support 

 Strahl's ohservations. while in his se<'oiid. paper (Xo. 7) lie seems to 

 have somewhat modified his idea. For the exact details in which his 

 later ideas difler from those of Perenyi(Xo. 1 ()), T must refer the reader 

 to the original papers themselves, as I have to confess my inahiliiv 

 lo grasp them ))recisely. Xotwifhstaniling Perenyi's sfateiiuMit 

 that thev dilfer, it appears to me that they are deserihing snl)stan(ially 

 the same process. Under the circumstances, I am unahle to sa\' 

 wdiether my results agree with the view of either or IxHh of these 

 aiitliors, although I think we have arrived at^ nearly the same 

 results, Hoffmann says that the origin of the allantois in Reptilia is 

 tlu'onghoiit the same as in lîirds (X'o. 7. ji. ISO). Such is the eon- 

 elusion r too have arrived at, after a eareful study oi' ("helonia. 

 In fact, ihis is so much so that (Jasser's figures (Xos. \'2 atid l."!) oi- 

 lîalfoiir's deseriplioii (Comp. Emhrvol. \'ol. If.) on the origin of 

 the allantois in liii-ds tnight lie hodil\ adopte(l to desia-iiic tiie same 

 process in ('lielonia. 



As I lia\'e a more f'oinplete sei'iev of the 'frionvx emhryos 



