FISHES PERCIDAE POMOXIS NIT1D0S. 



which is nearly equal to the first soft and articulated ray. Of the latter we observe fifteen, the 

 posterior five diminishing gradually in height. The soft portion of that fin is a great deal 

 more developed than the spinous portion. The same is the case with the anal, which has like- 

 wise six spiny rays, increasing in depth from the first to the sixth, which is shorter than th 

 first articulated ray. The external margin of the fin is rounded. Its anterior spine is situate 

 opposite the fourth dorsal one ; but since the entire base of the anal fin is equal to that of the 

 dorsal, the posterior margin of the anal extends further backwards than the dorsal. The caudal 

 fin enters four times and a half in the total length ; its posterior margin is sub-concave, and its 

 lobes sub-angular. The origin of the ventral fins is opposite the inferior edge of the insertion 

 of the pectorals, hence situated .slightly backwards with reference to the latter. A stout and 

 acerated spine may be observed upon their anterior or external margin, considerably shorter 

 than the first soft ray. When these fins are brought into contact with the abdomen, their 

 extremities project beyond the origin of the anal fin, and consequently overlap. the vent. Even 

 the tips of the ventrals extend beyond a vertical line drawn through the origin of the anal fin. — 

 Br. VI : VIII ; D VI, 15 ; A VI, 17 ; C 8, 1, 8, T, 1, 6 ; V i, 5 ; P 15. 



The soft rays of the dorsal and anal fins bifurcate twice, whilst those of the caudal, ventrals, 

 and pectorals exhibit subdivisions of the third degree. The lateral line is arched, following in 

 that respect the curve of the back. 



The scales are well developed and ciliated upon their external (posterior) margin. They 

 difier considerably in shape, according to the regions to which they belong. In the lateral line 

 (fig. 1) they are longer than deep, and upon the dorsal and abdominal regions deeper than long, 

 (figs. 6 and 8). Diverging grooves are observed upon the anterior section of the scale only. 

 Exiguous or attenuated scales may be observed upon the base of the caudal, extending to a 

 certain distance along the rays, a feature not represented on the figure. 



The upper regions of the head and body are reddish or brownish, the head uniformly so, the 

 back presenting obsolete, transverse blackish bands of fasciaj, composed of agglomerated small 

 spots. The same spots maybe traced upon the dorsal and caudal fins. The inferior regions 

 are yellowish brown, with either a silver or a golden hue. The anal fin is occasionally spotted ; 

 the ventrals and pectorals are unicolor. A black spot may be seen upon the upper and posterior 

 part of the opercle. 



References to the figures. — Plate II, fig. 5, represents a profile view of Fomoxis nitidus. 

 Fig. 6 is a scale from the dorsal region ; fig. 7 a scale of the lateral line, and fig. 8 a scale 

 from the abdominal region. 



The scales are somewhat magnified for the purpose of exhibiting their structure. They are 

 taken upon the same vertical line, corresponding, generally speaking, to the greatest depth of 

 the body. 



List of specimens. 



