No. 6.] AMERICA* .IfOA'PtfOLOGSCAL SOCIETY. 337 



prostomium to pygiclium. Purely vegetative organs (e.g., mouth, 

 alimentary canal, anus, and nephridia) are absent, although a 

 rudiment of the alimentary canal may exist as a median strand 

 of tissue extending the length of the bud. 



The youngest buds form a cluster of about twenty-five 

 attached to the right side of the zone of proliferation, on its 

 ventral aspect. The earliest-formed organs are the anal cirri, 

 at first two distal protuberances which elongate and become 

 moniliform before the bud segments. Apparently the bud 

 contains only ectoderm and mesoderm, which are continuous 

 with the same germ layers of the proliferating region. 



In neither species are there any reproductive cells in the 

 body of the parent anterior to the proliferating region, but 

 sperm cells are present in T. gemmipara in the twenty parental 

 somites back of this point. 



VIII. AMPHIBIAN STUDIES. 



J. S. KINGSLEV. 



THE following are the chief points made in the paper : 



1 . The Salamandrina form the central Urodele stem, and the 

 Perennibranchs and Derotremes have been derived from this 

 stem by degeneration and the retention of larval characters. 



2 . The Urodeles cannot have been the ancestors of the Anura ; 

 the anuran tadpole resembles the Urodele only in superficial char- 

 acters ; the Anura have descended directly from the StegoccpJiala. 



3. Amphiuma has no tentacular apparatus at any stage; 

 what was described as such by Davison was a trematode 

 parasitic in the suborbital blood vessel. 



4. The Caecilians differ from all Urodeles in the fact that 

 the palatine nerve receives a branch from the ophthalmicus 

 profundus instead of from the maxillaris superior nerve. 



5. The Caecilians have not descended from the Urodeles, nor 

 is Amphiuma a neotaenic Caecilian. The Caecilians are degen- 

 erate in loss of limbs and tail ; in all other respects they are the 

 most primitive of living AmpJiibia. 



