( 47 ) 

 RECORD 



OF CURRENT RESEARCHES RELATING TO 



INVERTEBEATA, CRYPTOGAMIA, MICROSCOPY, &c.* 



ZOOLOGY. 



A. GENERAL, including' Embryology and Histology 



of the Vertebrata. 



Development of the AUantois and the Gastrula of the Verte- 

 brata. t — A short time ago Professor Kuppfer (with Professor 

 Benecke) examined the development of Lacerta agilis and Emys 

 europcBa, and observed the development, by invagination of the ecto- 

 derm, of a blindly ending sac, the relations of the orifice of which were 

 the same as that of the prostoma (or gastrula-mouth) of Amphioxus, 

 and of the anus of Eusconi in the Batrachiaus ; or, in other words, the 

 gastrula-cavity was in these Eeptilia found to communicate with the 

 medullary groove. This gastrula-cavity does not, however, become 

 converted into the primitive enteron, and its epithelium does not 

 become connected with the enteric glandular layer ; longitudinal 

 sections revealed the fact that the gastrula-cavity of the Chelonian 

 embryo was continued into the hind-gut, and that, therefore, it formed 

 the rudiment of the allantois. 



Returning to the subject last summer, Kuppfer made a series of 

 sections with the view of determining the relations which subsist 

 between tlie allantois and the medullary tube ; starting from behind, 

 he found that in his first three sections the dorsal medulla was solid ; 

 in the fourth there was a cleft-like lumen, and in it and in the next 

 three it was possible to make out a canal which took a ventral 

 direction from the floor of the central canal and opened into tho 

 epithelial sac of the allantois ; that is, the allantois is j^rovided with 

 a hollow stalk which passes into the dorsal medulla. This " myelo- 

 allautoid " canal is covered by a regularly arranged cylindrical 

 epithelium, and bus on either side an umbilical vessel. This im- 

 portant discovery allows us to carry tho gastraea theory into tho great 

 division of the Amniote Vertebrata, and does much to explain tho 

 phylogenctic history of the allantois. 



Describing \ tho gastrulation of the salamander, Kuppfer points 

 out that the gastrula-mouth does not appear until two ridges havo 



* <rs~ It should be understood that the Society do not liold tlicnisclvcs respon- 

 sible for tlic views of the authors of tho papers, &c., referred to, nor for the iminnrr 

 in which tlioso views may be expressed, tlio object of the Ro(H)rd beiii^ to presi nt 

 a Bumraary of the papers as actually publishcJ. Objections and corrections should 

 therefore, for the most part, be addressed to tlie authors. 



t 'Zool. Anzeifjor,' ii. (1879) p. 520. 



X Loc. eit., p. 59:i 



