CONTRIBUTIONS 



TO 



NORTH AMERICAN ICHTHYOLOGY. 



No. 2. 



A.-NOTES ON COTTIDi], ETHEOSTOMATID^, PERCID^., CEN- 

 TRARCHID^, APHODODERID^, UMBRIDi], ESOCID^E, 

 DOHYSOMATIDiE, CYPRINID^, CATOSTOMIDi], AND HY- 

 ODONTIDiE, WITH REVISIONS OF THE GENERA AND 

 DESCRIPTIONS OF NEW OR LITTLE KNOWN SPECIES. 



COTTID^. 



1. COTTOPSIS SPILOTUS, {Cope) J or. 



Uranidea spilota, Cope, Proc. Ac. Nat. Sci. Phila. 1865, 82. 



Cottopsis ricei, Nelson, Bull. Ills. Trans. Nat. Hist., 1876. — Jordan, Proc. Ac. Nat. Sci. 

 Pbila. 1877, 61. 



An examination of the types of U. spilota shows their probable iden- 

 tity with Mr. Nelson's species as above indicated. Prof. Cope's speci- 

 mens are in bad condition, and have lost the peculiar dermal spines. 

 Prof. Gill thinks that Cottopsis spilotus and Cottopsis semiscaher Cope 

 are not truly Cottopsis, the only species properly referable to that genus, 

 being G. asper Rich, (of which C. parvus Grd. is the young). At auy 

 rate, C. spilotus and C. semiscaher form a well-marked group or section 

 intermediate between Cottopsis and Potamocottus. 



ETHEOSTOMATIDJ]. 



2. AMMOCRYPTA BEANII, gen. et sp. nov. 



Generic characters.— AlWed to Pleiirolepis Agassi z. Body greatly 

 elongated, subcyliudrical, and translucent. Head as in Fletirolepis, but 



