1817.] GENUS CATOSTOMUS. 105 



12. C. Duqitesnii. Head large and long; month wide; 

 ^ca/^^ large, subtrilobate . dorsal Jin quadrangular; the cwa/ 

 Jin extends as far as the base of the caudal Jin ^ which is 

 greatly forked; lateral line arched at the centre of the 

 body. 



Body long, a little compressed: snout strong; the mouth 

 is furnished with thick, plaited, and very large lips; pecto- 

 ral Jins pretty large; the scales are strong, greatly radiated, 

 and as wide again as long — they are of nearly an equal 

 size on the whole body; the lateral line forms a long cur- 

 vature towards the back; lobes of the caudal Jin pointed, 

 the upper lobe somewhat the largest; length from the snout 

 to the extremity of the caudal fin nineteen inches; depth 

 three inches and a half; thickness two inches; the head 

 measures about one fifth part of the whole fish. 



p. 17.— D. 14.— V. 10.— A. 9.— C. 18! rays. 



This new species is so strongly marked that it will be 

 easily distinguished from the foregoing. 



It inhabits the Ohio; and was discovered at Pittsburg, 

 t^e ancient Fort Duquesne, by Mr, Thomas Say. 



It was not until the publication of the first part of 

 this Monograph, that I noticed the above described spe- 

 cimen in the collection of the Academy of Natural Sci- 

 ences of Philadelphia. 



Of the above twelve species, and likewise of the Bo8- 

 toniensis, I have drawings; and part of them are already 

 engraved for my projected work on the Fishes of the 

 United States of America. But in order to facilitate a com- 

 parison of those species described by others with mine, 

 and chiefly to incite to a re-examination of the subjects 

 themselves, I have concluded to append to this paper the 

 descriptions which follow% The reader by this means will 



