298 BULLETIN 188, UNITED STATES NATIONAL MUSEUM 



dorsal profile from nape to tip of snout evenly curved, its width 0.6 its 

 depth ; snout strongly compressed, less than 0.5 length of head, slightly 

 overhanging the mouth ; bifid spine inserted under and slightly ante- 

 rior to the eye, its larger prong extending to a point under pupil; 

 nostrils nearer to tip of snout than to eye, the anterior nostiil in a 

 short tube with a fringed margin, the opening inclined obliquely 

 forward; posterior nostril simple, elongate; eye almost wholly in 

 anterior half of head, touching dorsal profile, two in snout, five in 

 head and two in interorbital space; mouth very small, strongly arched, 

 its width less than diameter of eye; six subequal barbels, one rostral 

 pair on front of snout, two maxillary pairs somewhat less than diam- 

 eter of eye, one arising from groove over posterior part of maxillary, 

 one from groove at posterior end of maxillary. 





Figure 61. — Ngacanthopsis gracilentus, new species: Type (U.S.N.M. No. 107952). Drawn 



by Mrs. Aime M. Awl. 



Squamation : Scales minute, none on head ; lateral line present only 

 on anterior fourth of body. 



Fins : Origin of dorsal nearer base of caudal than tip of snout, over 

 base of ventrals; dorsal rays ii,7, longest ray 0.8 head; caudal fin 0.9 

 head, its posterior margin truncate; anal rays ii,5, longest ray 0.7 

 head; ventral rays 7, longest 0.7 head; pectoral rays i,9, longest 0.6 

 head. 



Coloration (in preservative) : Generally pale yellowish brown; a 

 series of about 16 small roundish dark brown spots along axis of 

 body ; back vermiculated with brown, and about 13 dark brown spots 

 on the middle of the back between head and caudal fin ; top of head 

 spotted with brown ; a series of 5 or 6 small round dark brown spots 

 along side of head under eye; caudal fin with 6 obscure cross bands 

 of dark brown spots, a small round glistening black spot on the upper 

 base of the fin, and a much less distinct corresponding brown spot on 

 the lower base of the fin ; fins otherwise plain. In life the black spot 

 on the upper caudal base was surroimded by pale orange and the 

 caudal fin was pale red, with dark brown spots on the rays. 



