FISHES — CYPRINIDAE CATOSTOMUS MACROCHEILUS 



225 



the inferior surface of tlie head and abdomen being yellowish or whitish. The specimen before 

 us measures fifteen inches in total length. 



List of specimens. 



3. CATOSTOMUS MACROCHEILUS, Grd. 



Spec. Char.— Head constituting the fifth of the total length. Eye of medium size. Mouth large, provided with large lips 

 and conspicuous labial papillae. Isthmus very broad. Dorsal fin much longer than high ; its anterior margio neariy equi- 

 distant between the extremity of the snout and the insertion of the caudal. Insertion of ventrals situated opposite the anterior 

 third of the dorsal, and nearer the extremity of the snout than the tip of the lower lobe of the caudal. Posterior extremity 

 of the anal extending beyond the rudimentary rays of the caudal, which is posteriorly crescent-shaped. Scales rather large. 

 Bluish black above ; whitish beneath. 



SvN. — Catoslmnus macrochdlus, Gbd. in Proc. Acad. Nat. Sc. Philad. VIII, 1856, 175. 



This species is very different from the preceding two ; the head is larger and more elongated ; 

 the mouth larger, and hence much larger lips, covered with large papillae. The scales which 

 cover the body are larger than in C. occidenialis, and smaller than in C. laUatus. The head 

 constitutes the fifth of the total length ; the horizontal diameter of the eye is contained nearly 

 six times in the length of the side of the head. The head itself is sub-quadrangularLy pyramidal, 

 anteriorly truncated with the upper edge of the snout projecting. The anterior margin of the 

 dorsal is a little nearer the end of the snout than the insertion of the caudal fin ; its upper 

 margin is concave ; its base enters over six times and a half in the total length. The anal is 

 well developed, for, its tip extends beyond the base of the caudal. The ventrals are inserted in 

 advance of the middle of the dorsal. The pectorals are large and elongated. 

 D 2, 14 + 1 ; A 1, 8 ; C 5, 1, 8, 8, 6 ; V 11 ; P 18. 



The scales are nearly as deep as long, irregularly rounded, well imbricated, with radiating 

 grooves upon their anterior and posterior sections. The specimen observed measures sixteen 

 inches in total length. 



The dorsal region above the lateral line is bluish black ; a darker broad streak may be traced 

 along and below the lateral line, over the side of the head across the orbit. The rest of the 

 flank is of a metallic yellow, which extends similarly over the side of the head, the inferior 

 surface of which, as well as the abdomen, are whitish. 



List of specimens. 



29 a 



