218 DEEP SEA FISHES. 



upper angle of the opercle, little forward of the bases of the pectorals ; 

 number of spines usually eleven, rarely ten ; second spine smooth, including 

 the filament it is three fifths as long as the head. Spines of the second dor- 

 sal weak and small ; origin of the fin distant from the first dorsal hardly less 

 than the length of the latter's base. Anal origin little farther backward 

 than the base of the first dorsal. Ventrals small, first ray with a filament, 

 equal in length to the distance from the tip of the snout to the middle of 

 the eye, inserted at the lower angle of the opercle. Caudal filamentary 

 when complete. In most cases it is truncate at the base, which bears a 

 group of rays, of varying number, terminating in a j^encil point. The tuft 

 on the tail gives a completed appearance to that organ, but the length of 

 the caudal section varies greatly ; on six specimens there are respectively, 

 58, 70, 76, 81, 103, and 105 rays in the second dorsal, and Gl, 74, 78, 83, 

 106 and 107 in the anal fins. Only about one in six is entire. Pectorals 

 small, more than half as long as the head, inserted a little backward of the 

 ventrals or of the origin of the dorsal. Vent close to the anal fin. Scales 

 medium, rough with several to five or more spinose ridges which are diver- 

 gent backward ; five scales between the lateral line and the dorsal fin. Py- 

 loric appendages ten. Females of six and one half inches have both ovaries 

 developed and filled with eggs that are nearly or quite mature. 



Sides of the muscular regions flesh color to brown, darker on the back, 

 with more or less of silver especially on the sides of the body chamber. 

 Belly from anal to chin blackish. Entire head translucent (possibly lumin- 

 ous), silvery, around eyes and gill openings showing blackish as from within. 

 Forward ends of rostral angles blackish. Puncticulations of brown are irreg- 

 ularly scattered or grouped everywhere over head and body. 



Trachyrhynchus helolepis. 



Trachyrhynchus helolepis Gilb., 1891, P. U. S. Mus., 5G2. 



Plate G,fig. 2; Plate LI., shull. 



Br. r. 7 ; D. 11 (11-10), + ca. 113 ; A. ca. 107 ; V. 7-6 ; P. 23. 

 Depressed and acute anteriorly ; compressed, narrow and tapering to a 

 slender extremity in the posterior half. Head one fifth wider than deep, 



