14 Mr. J. 11. Norman— A Revision 



part of anterior arch. Scales 56/13 ; ventral scutes 2v), 

 weak. Dorsal 11 ; origin miicli nearer base of caudal than 

 upper end of pectoral base. Anal 65; origin equidistant 

 fi'om base of caudal and tip of lower jaw; length of base 

 25 in length of body. Pectoral longer than head. 



N.W. Ecuador. 



A single specimen from the E-io Vaqueria, 226 mm. in 

 total length ; type of the species. 



5. Opisthopterus macrops. 



Pridigaster macrops, Giiuth. Proc. Zool. Soc. 1866, p. 603; Cat. Fish. 



Yii. p. 461 (1868J. 

 Opisthopterus macrops, Jord. & Everm. Bull. U.S. Nat. Mus. xlvii. 



1896, p. 437. 



Depth of body 3 in the length, length of head 4|. Ventral 

 profile much more convex than dorsal ; dorsal protile of head 

 concave. Snout shorter than diameter of eye, which is 2J in 

 length of head ; maxillary extending to below anterior half 

 of eye ; posterior supramaxillary extending to posterior end 

 of maxillary ; lower jaw very oblique, strongly projecting. 

 Kidges on head diverge posteriorly. 19-20 gill-rakers on 

 lower part of anterior arch. Scales 58/17; ventral scutes 

 28. Dorsal 13; origin a little nearer upper end of pectoral 

 base than base of caudal. Anal 61; origin much nearer tip 

 of lower jaw than base of caudal ; length of base twice in 

 length of body. Pectoral about equal to head. A black 

 scapular spot. 



Pacitic Coast of Panama. 



A single specimen, 190 in total length; type of the 

 species. 



3. Pkistigaster, Cuv., 1817. 



Kegne Auim., ed. 1, ii. p. 176. 



Fristigaster (part), Gunth. Cat. Fish. vii. p. 460 (1868). 



Differs from Opisthopterus in the greater depth of the bodj^ 

 with the abdominal profile very convex. Four or five supra- 

 neural spines between occiput and origin of dorsal. Origin 

 of dorsal in front of that of anal. Scales without trans- 

 verse grooves. 



A single species from tropical South America. 



Fristigaster cay anus. 



Fristif/aster aiyanus, Cuv. Kegne Anim,, ed. 1, iv. pi. x. fig. 3 (1817) ; 

 Cuv. & Val. Hist. Nat. Poiss. xx. p. 334, pi. 597 (1847) ; Gunth. 

 Cat. Fish. vii. p. 463 (1868); Jord. & Everm. Pull. U.S. Nat. Mus. 

 xlvii. 1896, p. 438. 



