86 



that of the highest. This fin, Hke the anal, is enveloped in a mem- 

 brane so thick as to render the enumeration of the rays difficult ; 

 the tips of the rays are free. 



The anal, coterminal with the dorsal, is in length equal to half 

 the distance from the front of the head to the fork of the caudal 

 fin. The height anteriorly, is not quite half that of the dorsal ; 

 the height posteriorly is about equal to that of the dorsal. 



Pectorals long and pointed, their height being a little more than 

 one-fourth the length of the fish. 



Caudal deeply forked, the central rays being very short, the 

 height of the external ones equal to the length of the head. 



The scales extend up on the membrane, covering the dorsal, anal 

 and caudal fins. 



D. 45, P. 21, A. 31, C. 5, 1, 9, 8, 1, 5. 



This species is by no means common in this vicinity, only three 

 or four specimens having been obtained in the course of seven 

 years. ^ It is allied very closely indeed to P. triacanthus of the 

 Atlantic coast, which species it represents in our waters. Slight 

 differences in the form of the front of the head, in the proportions 

 of the dorsal and anal fins, and in the development of the horizon- 

 tal spines, and the absence of the black points on each side of the 

 dorsal fin, appear to be the only distinguishing features. It cer- 

 tainly approaches more closely to its eastern ally than almost any 

 other fish of our waters. 



The figure does not give the outline of the abdomen correctly ; 

 it should follow the regular curve of the remainder of the lower 

 border. 



This species is evidently of the same genus as the Atlantic P. 

 triacanthus, and I have accordingly called it Poronotus ; but as I 

 have been unable to examine any diagnosis of that genus, I do so 

 with doubt, inasmuch as the name indicates a character which I do 

 not find in my specimens. Until the reception of Mr. Gill's " Cat- 

 alogue of the Fishes of the Eastern Coast of North America," my 

 manuscript notes recorded it as Peprilus simiUimus. 



