84 PROCEEDINGS OF THE ACADEMY OF 



cavated triangle ; each separately is semi-claviform. Their upper surface 

 is covered with small teeth, and along the internal margin with a row of 

 scarcely recurved more elongated ones. The upper pharyngeals are also 

 clothed with small teeth, besides which, on the median bone, are conical 

 ones like those of the lower bones. The first branchial arch is externally 

 furnished with compressed setae, which are muricated on their internal bor- 

 ders ; internally, they have transverse thick ridges with villiform teeth, 

 like those of the other arches ; the external rows of ridges are larger than the 

 internal. 



The scales of this genus are arranged in nmeh less oblique lines than in most 

 of the other representatives of the subfamily of Scicenince. An oblique row in 

 the typical species extends from the commencement of the second dorsal to 

 that of the anal. 



This genus has been established for the Perca argyroleuca of Dr. Mitchill, or 

 the Corvina argyroleuca of Cuvier and Valenciennes, and the allied species 

 chiefly found in the Caribbean and neighboring seas. The Homoprion xanthu- 

 rus of Holbrook, or Homoprion subtruncatus, perhaps belongs to this genus also, 

 but as it is said to have " two or three series of small, pointed, recurved, card- 

 like teeth, with an outer row of larger, conical, pointed teeth" in both jaws, 

 it is not deemed advisable to positively place it there. The specimens referred 

 to under that name by Dr. Girard, in the "Report on the Ichthyology of the 

 Mexican Boundary Survey," as preserved in the Smithsonian Institution, be- 

 long to the Bairdiella argyroleuca. We have examined five of the specimens 

 labelled as Homoprion xanthurus, and have counted the number of rays of the 

 second dorsal fin. There are one spinous and twenty or twenty-one articulated 

 rays, the last of which is double. They therefore agree in the number of rays, 

 as well as in appearance, with the Bairdiella argyroleuca. The Homoprion 

 subtruncatus has thirty-two articulated dorsal rays. A variation equalling a 

 third of the greatest number of rays is rarely found in the same natural genus. 

 Yet there is a very close resemblance between that species and the type of 

 Bairdiella. It certainly shows much more affinity to the latter externally 

 than to the Homoprion lanceolatus. 



This genus is less nearly allied to Corvina ; it differs in form, squamation and 

 the dentation of the margin of the preoperculum. The genus Stellifer of Cu- 

 vier is founded on the Bodianus stellifer of Bloch, a species supposed to belong 

 to this group, but which cannot be positively identified. 



Type. Bairdiella argyroleuca Gill. 

 Syn. Bodianus argyroleucus Mitchill. 

 Corvina argyroleuca Cuv. et Val. 



Genus Corvina Cuv. 

 Corvina Cuv., Regne Animal, ed. ii. vol. ii. p. 173. 1829. 



Body oblong rhombo-ovate, with the ante-dorsal region slightly curved, and 

 thence declining in a straight line to the snout. The subdorsal region declines 

 with a slight curve backwards. 



Head oblong, with the snout rather high and truncated. The profile is 

 straight and rapidly declivous. Eyes anterior, subcircular. Preoperculum 

 scarcely dentated ; mental pores well developed. Mouth subterminal and 

 nearly horizontal. Supramaxillary bones well exposed and terminating before 

 the hinder border of the orbit. 



Teeth in a moderate band in each jaw ; that of the upper preceded by a 

 row of larger ones. 



Anterior dorsal fin with about ten spines ; the second long. Second anal 

 robust. 



The variable teeth of the lower and median upper pharyngeal bones are 



[April, 



