28 [March, 



15. Catostomus plebeius, B. and G. Body subfusiform, compressed. Head 

 elongated, subcorneal, forming the fifth of the entire length. Mouth of medium 

 size. Eyes large, subelliptical, their longitudinal diameter being contained 

 about five times in the length of side of head. Dorsal fin subquddrangular, its 

 anterior margin being equi-distant between the tip of snout and the first rudi- 

 mentary rays of the upper lobe of the caudal. The latter is slightly concave 

 posteriorly, and the lobes rounded off. The base of the anal is contained nearly 

 three times in its height, and when brought backwards its tip extends to the ru- 

 dimentary rays of the inferior lobe of the caudal fin. The ventrals are inserted 

 under the posterior, third of the dorsal, bent backwards their tip does not reach 

 as far as the anus. The pectorals are of medium development, subovate, pointed 

 posteriorly. 



D I. 9+1. A I. 7. C 3. I. 8. 8. I. 2. V 8. P 14. 



The scales are of medium size, considerably the largest on the peduncle of 

 the tail. Twenty-eight to thirty rows from the base of the ventrals to the dor- 

 sal fin. About eighty in the lateral line, which is not discernible as far as the 

 base of caudal fin. 



The color, as preserved in alcohol,' is dark brown on the upper regions, faintly 

 mottled with blackish patches. The sides and belly exhibit traces of orange in 

 some of the specimens, in others it is pale yellowish. The fins are unicolor, 

 the dorsal, caudal, and pectorals blackish brown ; the anal and ventrals 

 yellowish. 



Rio Mimbres, trib. of Gila. John H. Clark. 



16. Catostomus tnsignis, B.andG. Subfusiform, elongated, compressed. Head 

 forming two-ninths of the total length. Mouth of medium size, surrounded with 

 considerably developed lips. Eyes large, subelliptical; their longitudinal diam- 

 eter contained almost six times in the length of side of head. The dorsal fin is 

 subquadrangular, its anterior margin is situated midway between the snout and 

 base of caudal fin. The latter is posteriorly forked, with its angles subacute. 

 The anal is quite narrow and elongated, its base enters three times in the length 

 of its anterior margin. The ventrals are inserted under the posterior half of the 

 dorsal, their tip posteriorly does not reach the vent. The pectorals are elonga- 

 ted, their tips not extending as far back as the anterior margin of the dorsal. 



D II. 11. A II. 7+1. C 3. I. 8. 8. I. 3. V 10. P 18. 



The scales are large, there are twenty rows between the base of ventrals and 

 the dorsal line. The lateral line takes a straight course along the middle of the 

 sides and is composed of about sixty scales. 



The color, as preserved in alcohol, is dark reddish brown above and on the 

 sides, lighter beneath. There is a black dot at the base of each scale, giving a 

 dotted appearance to the body. The fins are unicolor. 



Rio San Pedro of the Rio Gila. John H. Clark. 



17. Cailpiodes tumidtjs, B. andG. Head forming four-nineteenths of the total 

 length. Snout conical. Mouth very small and protruding. Lips small. Eyes 

 very large, their diameter contained four times in the length of side of head. 

 Anterior margin of dorsal equi-distant between the tip of snout and base of cau- 

 dal, the posterior portion of which is very low. Tip of anal extending to base 

 of caudal. Tip of ventrals reaching as far back as the vent. Tip of pectorals 

 extending almost to base of ventrals. Caudal fin forked, and about the same 

 length as the head. 



JJ II. 27. A II. 9. C 5. I. 8. 8. I. 4. V II. 9. P 16. 



Thirteen rows of scales may be counted on the line of greatest depth, and 

 thirty-seven or thirty-eight scales on the lateral line. 



Color lisjht reddish brown above and yellowish white beneath. 

 Near Fort Brown, Texas. John H. Clark. 



18. Gila gibbosa, B. and G. Body rather thick; dorsal region between dorsal 

 and occiput more arched than generally observed in the genus. Head forming a 

 little less than the fourth of the entire length ; greatest depth nearly equal to the 

 length of head. Eyes quite large, their diameter contained five times in the 

 length of the side of head. Anterior margin and dorsal nearer to the base of 



