Jordan and Evermann. Fishes of North America. 965 



441. RHOMBUS, Lac6pede. 



(BUTTER-FISHES. ) 



Rhombus, LACEPEDE, Hist. Nat. Poiss., ir, 321, 1800, (alepldotus). 



/Vjin/ns, CUVIER, Regne Anim., Ed. 2, Vol. n, 213,1829, (longlpinnis). 



Poronotus, GILL, Cat, Fish. E. Coast N. A met., 1861, 35, not characterized, (Iriacanthm); Pror. 



Am. Phil. Soc., xxi, 670. 1884, (diagnosed). 

 Palomela, JORDAN & EVERMANN, new subgenus, (palometa). 



Body ovate or suborbicular, strongly compressed, tapering into a slen- 

 der caudal peduncle, which is not keeled or shielded. Head short, com- 

 pressed, the profile obtuse. Mouth small, terminal, the jaws subequal. 

 Premaxillaries not protractile. Jaws each with a single series of weak 

 teeth. Scales very small, cyloid, silvery, loosely inserted, extending on 

 the vertical fins. Opercular bones entire. Gill membranes separate, free 

 from the isthmus ; gill rakers moderate. Lateral line continuous, con- 

 current with the back. Dorsal fin long, more or less elevated in front, 

 preceded by a few indistinct spines usually one or more procumbent 

 spines in front of dorsal and anal, each of these with a free point both 

 anteriorly and posteriorly; anal fin similar to dorsal, or shorter, usually 

 with three small spines; ventral fins wanting; a single small, sharp 

 spine, attached to the pubic bone, occupying the place of the ventrals ; 

 pectorals long and narrow; caudal widely forked. Species few, mostly 

 American. This genus differs from Stromateus chiefly in the prominence 

 of the pelvic bone, which projects as a lamina beyond the skin. Species 

 of Stromateus occur in Europe and South America, but none within our 

 limits. (p6/u(3oc, a rhomb or diamond, from the form of the body.) 



RHOMBUS: 

 a. Dorsal and anal fins very high in front, the anterior lobe falcate; body suborbicular. 



b. Dorsal rays III, 45, anal rays III, 43. PARC, 136". 



66. Dorsal rays about III, 40; anal rays about III, 39. XANTHTJRUS, 1364. 



aa. Dorsal and anal fins moderately elevated in front, the anterior lobe scarcely falcate. 

 PALOMETA (Spanish name from Paloma, a dove): 

 r. Sides of back without conspicuous series of pores above lateral lino. 



(1. Anal rays III, 45; body ovate, the depth half its length. PALOMETA, 1365. 



dd. Anal rays III, 32 to 39. 



e. Body broad ovate, the depth rather more than half the length; A. Ill, 32. 



MEDIITS, 1366. 



ee. Body elliptical, the depth not half the length; A. Ill, 39. SIMILLIMUS, 1367. 

 PORONOTUS (Tropos, pore; J/WTO?, back): 

 cc. Side of back above lateral line with a series of large, wide-set pores. 



/. Body elliptical, the depth 2% in length; anal rays III, 37. TRIACANTIIUS, 1368. 



Subgenus RHOMBUS. 

 1363. RHOMBUS PARU (Linnaeus). , 

 (HARVEST FISH.) 



Head 3 ; depth 1|. D. Ill, 45 ; A. II, 43 ; scales about 90 ; vertebrae 

 15 -f- 15. Body suborbicular, bounded by even curves ; mouth very small, 

 oblique; maxillary reaching front of orbit. No pores along sides of 

 back. Dorsal and anal fins falcate, the length of their longest rays 



