THE OPHTHALMIC AND EYE MUSCLE NERVES OF 

 THE CAT FISH (AMEIURUS).* 



By I. S. Workman. 



With one figure in the text. 



In the fishes, as is well known, there are three ophthalmic 

 nerves — the ophthalmicus superficialis facialis (a lateral line 

 nerve), the ophthalmicus superficialis trigemini (general cutane- 

 ous), and the ophthalmicus profundus, the latter in some elasmo- 

 branchs being a separate nerve arising cephalad of the trigeminus. 



The ophthalmicus profundus is typically absent in the bony 

 fishes, the only exceptions thus far recorded being Trigla (ap- 

 parently the root and ganglion only, Stannius '49, p. 25), 

 Clarias and Trichomycterus (Pollard, '95), Ameiurus (Wright 

 '84), Silurus (Juge, '99), and probably Menidia (Herrick, '99, 

 sec. 7, XI). Allis, however, has expressed doubt as to whether 

 the nerve described by Pollard in siluroids as. the ophthalmicus 

 profundus is not really the ophthalmicus superficialis trigemini, 

 and a study of Wright's account of Ameiurus led Herrick to 

 the same conclusion. 



To clear up this and some other discrepancies in the de- 

 scriptions of the nerves of the orbit of the siluroid fishes, serial 

 sections were cut through the head of the small stone cat fish, 

 Ameiurus melas Raf., and stained by the Weigert process. 

 The results of the examination of these sections were controlled 

 by dissections of the blue fish, Pomatomus saltatrix L. The 

 latter is a typical teleost, while it is generally admitted that the 

 cat fishes are decidedly aberrant. 



Inasmuch as the distribution areas of the superficial and 

 deep ophthalmic branches of the trigeminus are often very simi- 

 lar (note their peripheral anastomosis in some elasmobranchs), 



' Studies from the Neurological Laboratory of Denison University, under 

 the direction of C. Judson Herrick. No. XIII. 



