58 JOURNAL OF COMPARATIVE NEUROLOGY. 
ations which, when fully known, may throw light upon the 
particular points in question. The roots, ganglia and main 
trunks of the nerves of Amphibia in general have been faith- 
fully dissected, but the finer peripheral relations of these parts 
demand greater detail in description before any broadly com- 
parative evidence can be deduced upon the questions presented 
in this paper. The conclusions offered here are, therefore, 
based wholly upon my own observations and concern only Am- 
blystoma and Rana. 
CONCLUSIONS. 
I. In both Rana and Amblystoma there are two anasto- 
moses in the roof of the mouth between the general cutaneous 
component of the trigeminus and the communis component of 
the facial. These anastomoses take place through the palatinus 
VII which, in both cases, divides, sending one division lateral 
and the other mesal of the internal nares. 
2. The regions innervated respectively by the mesal and 
lateral branches of the palatinus VII through anastomosis with 
the general cutaneous component of the trigeminus correspond 
in the two genera. The branches of the palatinus VII must, 
therefore, be homologous each to each. 
3. The communicating nerve between the palatinus VII 
and ophthalmicus profundus V in Rana can not be homologous 
to the communicating nerve between the nerves of the same 
name in Amblystoma, since the former anastomoses with but 
one branch of the palatinus VII while the latter communicates 
with both branches of that nerve. 
4. The anastomosis between the general cutaneous com- 
ponent of V and the lateral division of the palatinus VII takes 
place through the maxillaris nerve in Rana and through the 
ophthalmicus profundus in Amblystoma. The function of the 
maxillaris in Rana is therefore performed in Amblystoma by 
the ophthalmic so far as the oral cavity is concerned. 
5. In cutaneous distribution, also, the function of the 
maxillaris in Rana is performed by the ophthalmic in Ambly- 
