3o8 Journal of Comparative Neurology. 



and probably in the former), but to have evoked in the medulla 

 oblongata special terminal nuclei, the " lobus trigemini," or 

 " tuberculum impar" of these fishes. 



The problem of the relation between the cutaneous and 

 the visceral fibers of the communis S3/stem I have touched upon 

 in another place. I do not claim to have settled it. It may- 

 be " unphilosophical " to associate these diverse structures in a 

 single system, but they are thus associated in our specimens 

 and we have not thus far succeeded in dissociating them. In 

 the present state of our knowledge it is better to stick to the 

 facts, whether they accord with theory or not. But even from 

 the theoretical standpoint it is difficult to account for the migra- 

 tion of general cutaneous fibers from the head into the trunk 

 in any such numbers as we find them in siluroids and other 

 forms with the accessory system well developed, for these re- 

 gions have their Own general cutaneous nerve supply from the 

 spinals. From the account of Harrison's dissections of the 

 gold fish ('95, p. 509), from the results of AUis ('97) and from 

 my own study of the recurrent nerve of Menidia, as well as 

 from the results presented in this paper, I am convinced that 

 this nerve supplies the terminal buds of the body and not the 

 general cutaneous areas. ^ This Cole seems to admit (p. 177) ; 

 his error lies in associating these organs with the ordinary so- 

 matic sensory nerves. We have no evidence that they are ever 

 supplied by the general cutaneous nerves. 



As for the motive for the migration of the terminal bud 

 system into the trunk, we can scarcely conjecture, as we have 

 no knowledge whatever of the function of these organs. The 

 lateral line system is very probably for the function of equili- 

 bration (see especially Lee, '98) and this would account for its 

 ramifications to the extreme dimensions of the body. The 

 terminal buds are also probably ectodermal in origin. If they 

 arose first as gustatory organs, their migration inwards in tiie 

 stomoda;uin tovvard the toncrue and teeth is intellieible. Whether 



1 Subsequent study of the cat fishes confirms this for the siluroids also 

 (Aug., 1900). 



