62. LETJCOSOMUS. 269 



nearly flat, equals the length of the snout. Snout somewhat 

 compressed, subconical. Mouth subhorizoutal, rather wide, the 

 maxillarjf extending to below the front margin of the orbit ; upper 

 jaw rather longer than the lower. Proeorbital very large, the other 

 suborbital bones narrow. The origin of the dorsal fin is nearly 

 opposite to that of the ventrals, and midway between the end of the 

 snout and the root of the caudal. Caudal fin forked. The pectoral 

 fins terminate at a great distance from the ventrals. There are four 

 longitudinal series of scales between the lateral line and central fin. 

 Silvery, membrane at the base of each scale blackish. Young with 

 an inconspicuous dark lateral band. 



Pharyngeal teeth 4 . 2 — 2 . 5 or 4, but slightly compressed, termi- 

 nating in a hobk. Gili-rakers very short, and few in number. The 

 attachment of the gill-membranes to the isthmus takes place oppo- 

 site to the angle of the proeoperculum. 



United States ; Canada. 



fl-6. Adult (18 inches long). Montreal. Purchased of Mr. Wright. 



c-d. Fine adult specimens. Canada. Purchased of Mr. Wright. 



e-h. Young. Canada. Purchased of Mr. Wright. 



i. Adult: stuffed. Canada. 



Tc-l. Young, Parmachenee Lake, Maine. Purchased of Mr. Wright. 



m. Adult. Bangely Lake, Maine. Purchased of Mr. Wright. 



n. Adult. Delaware River. Purchased of 0. Salvin, Esq. {Seniotilus 



rhotheus, Cope). 

 0. Adult female : skeleton. Montreal. Purchased of Mr. Wright. 



2. Origin of the dorsal Jin behind the root of the ventrals. 



6. Leucosomus corporalis. 



Cyprinus corporalis, MitchiU, Am. Month. Mag. ii. p. 824 ; Dekai/, 



Neiv York Faun. Fish. p. 21-3. 



atromaculatus, MitchiU, I. c. 



Leuciscus atromaculatus, Dekay, I.e. p. 210, pi. 32. fig. 102. 



iris, Cuv. ^- Val. xvii. p. 2oo, pi. 496. 



Semotilus atromacidatus, Girard, Proc. Ac. Nat. Sc. Philad. 1850, 



p. 204. 

 Leucosomus cataractus, (Baird) Cope, Proc. Ac. Nat. Sc. Philad.JSQl, 



p. 523. 

 Semotilus hammondii, Abbott, Proc. Ac. Nat. Sc. Philad. 1860, p. 474. 

 corporalis, Cojje, Journ. Ac. Nat, Sc. Philad. xiii. p. 362, pi. 10. 



fig. 2. 



D. 10. A. 10. V. 9. L. lat. 52-63. L. transv. 11|/13. 

 The height of the body is contained four times and a half in the 

 total length (without caudal), the length of the head thrice and 

 three-fifths. Head three-fifths as deep as long. The diameter of 

 the eye is one-sixth of the length of the head, one-half of that of 

 the snout, and less than one-half of the width of the interorbital 

 space, which is flattish. Snout obtuse, conical ; mouth rather wide, 

 the maxillary extending to below the front margin of the orbit ; 

 jaws nearly even in front. Suborbital bones of moderate width ; 

 prseorbital as long as deep, very much larger than the postorbital, 



