1884.] NATURAL SCIENCES OP PHILADELPHIA. 121 



A EEVIEW OF THE AMERICAN SPECIES OF THE GENUS TRACHYNOTUS. 

 BY SETH E. MEEK AND DAVID K. GOSS. 



In the present paper we give the synonymy of the species 

 of Trachynotus found in American waters, with brief de- 

 scriptions of those known to us found on the Atlantic Coast. 

 The latter are here all described from specimens obtained by 

 Professor Jordan at Havana and Key West. We are very much 

 indebted to Professor Jordan for use of his library and for 

 valuable aid. 



In the following analysis of species, Trachynotus marginatus is 

 omitted, the original description being too insufficient for com- 

 parison. Of the remaining seven species, two (rhomboides, 

 glaucus) appear to be confined to the Atlantic ; two others {ken- 

 nedyi, fasciatus) represent those on the Pacific Coast, while the 

 others (rhodopus, carolinus, cayennensis) appear to be found on 

 both sides, although in the case of rhodopus and carolinus being 

 far more abundant in the Atlantic. 



Analysis of Species of Trachynotus. 

 a. Dorsal with 19 to 20 soft rays ; anal with It to 19 soft rays. 

 b. Body very much compressed ; sides with narrow black cross- 

 bars ; lobes of vertical fins elongate, reaching past middle 

 of caudal fin in adult. 

 c. Snout subtruncate or nearly vertical ; profile from supra- 

 orbital to front of dorsal fin convex. glaucus. 1. 

 cc. Snout low, very oblique ; profile from supraorbital region 

 to the dorsal scarcely convex. fasciatus. 2. 

 bb. Body moderately compressed ; sides without narrow black 

 cross-bars ; lobes of vertical fins shorter, rarely reaching 

 base of caudal ; lobes of dorsal and anal usually 

 blackish. 

 d. Body broad, ovate ; the greatest depth at all ages more 

 than half length of bod}^ ; lobes of the vertical fins 

 reaching in the adult beyond the middle of their 

 fins. 

 e. Axil with a large black spot (in the adult) ; profile 

 strongl}' convex anteriorly. kennedyi. 3, 

 ee. Axil without dark spot ; profile from nostril to dorsal 

 everywhierp about equally convex. 

 9 rhomboides. 4. 



