166 CALIFORNIA ACADEMY OF SCIENCES 



bearing a well-developed, backvvardly directed spinous process. The lower caudal lobe is slightly 

 longer than the upper; the margin is concave rather than truncate, when the fin is spread. The pec- 

 torals are very short, reaching to or slightly beyond the vent in adults, a little longer in the young. 

 The fin is sharply angulated above, the third and fourth rays the longest; the posterior margin from 

 the fourth to the ninth rays is vertically truncate or slightly emarginate; the whole contrasting strongly 

 with the evenly rounded fin of P. horrens. The detached rays are short, the upper not nearly reach- 

 ing the tips of the ventrals. 



The dorsal contains invariably lo spines and 12 soft rays; the anal has 11 rays in all of the 

 eighteen specimens examined, except in one which had 10. 



Color in spirits: dark brown on back and sides, white below; a faint ill-defined dark bar 

 under spinous dorsal, and one slightly more distinct under posterior half of soft dorsal. Gill-cavity 

 blackish. Dorsals translucent, the spinous dorsal blackish toward tip anteriorly; posterior part of soft 

 dorsal dusky at base, the fin with a more or less distinct blackish margin, which does not involve the tips 

 of the rays. Caudal translucent dusky on basal portion, with faint dark blotches arranged in one or two 

 irregular cross-rows. In the terminal third, the rays become charged with much white pigment and 

 the intervening membranes are black. Anal and ventrals translucent, unmarked. Pectorals dusky 

 on basal half, becoming blackish toward middle of fin. The distal half of the third to the ninth rays 

 with a broad whitish bar, broadly margined with black. 



This species is now known from Panama, Mazatlan and Albatross Station 

 3041 (Magdaleua Bay, L. C). 



