30 U. S. p. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



SYH.—Perca (^Ltpibema) ckrysops, Rafin. Ichth. Oliiens. 1820, 22, and 23. 

 Ptrca mullilineata, Lesc. Mb. 

 Loirox inu/(i/mfo(us, Cl'v. & Val. Hist. nat. Poiss. 111,1829, 488.— Kirtl. in Bost. Journ. Nat. Hist. V, 1847, 



21. PI. vii. Fig. 1.— DeKat, New York Fauna, HI, 1842, 14.— Storer, Synops. 1846, 22. 

 Striped bass, gold eye, reck perch, rockjiah, rock bass, Vernacular. 



This being quite a common fish in the western rivers and streams, we have considered it a 

 desideratum among the illustrations accompanying this report. It is known under various 

 vernacular appellations, most commonly, however, under that of striped bass, especially in the 

 valley of the Ohio. 



This species has been described by various authors, as will be seen by referring to the above 

 synonymy. It is remarkable by its short, deep, and compressed body, the greatest depth of 

 which is a little less than the third of the entire length, whilst the greatest thickness is rather 

 more than the third of the depth. 



The head is of but moderate size, subconical when viewed in profile. It enters a little short 

 of four times in the total length. The mouth is medium sized ; the jaws sub-equal, the lower 

 one slightly protruding beyond the upper. The posterior extremity of the maxillary extends 

 to a vertical line which would be drawn midway between the anterior rim of the orbit and the 

 pupil. A few scales may be observed upon the dilated part of that bone. The tongue is 

 moderate and rather thin, provided upon its edge with velvet like teeth disposed upon a horse 

 shoe figure, the convexity of which is turned forwards. The eye is well developed and circular, 

 its diameter entering about four times and a half in the length of the side of the head. The 

 cheeks and preopercle are covered with scales somewhat smaller than those covering the rest of the 

 gill covers. The limb of the preopercle is finely serrated or denticulated. A flattened spine 

 may be seen across the opercle. There are six branchiostegal rays on either side ; the branchial 

 apertures themselves being continuous under the throat. 



The spinous dorsal fin is larger than the soft one ; it is sub-triangular in its outline, while the 

 latter is more of a trapezoid. The first spine is the smallest, the fourth is the highest ; they 

 diminish again from the fifth to the ninth ; the tenth spine is nearly equal to the eighth, and 

 belongs rather to the second than the first portion of the fin. The anal extends a little poste- 

 riorly to the soft portion of the dorsal ; it is preceded by three spines, the first of which is quite 

 small and acerated, the second nearly as deep as the third, but much stronger or stouter. The 

 posterior margin of the caudal is sub-crescentic, the fin itself constituting about the sixth of the 

 entire length. The insertion of the ventral fins is situated posteriorly to the origin of the dorsal 

 and the base of the pectorals. Their posterior extremity is far from reaching the vent which is 

 placed at a small distance from the anterior margin of the anal fin. The pectorals are broad 

 and sub-ovate, their extremities not "extending so far posteriorly as the ventrals. 



Br. VI : VI ; D X, 13 ; A III, 9 ; G 3, 1, 8, 7, 1, 2 ; V I, 5 ; P 16. 



The scales are rather large, disposed upon nineteen longitudinal series across the line of 

 greatest depth, six or seven above the lateral line, and eleven beneath it. The scales them- 

 selves are deeper than long, sub-truncated anteriorly, and rounded upon the remaining edges. 

 A few inconspicuous furrows may be observed upon the anterior section of the scales, whilst the 

 posterior section exhibits numerous minute prickles. Scales extend over the caudal and soft 

 portion of both the dorsal and anal fins. 



The upper region of the head and body is of an olivaceous tint, varying in shades, whilst the 

 sides are silvery, and the inferior region whitish. Longitudinal stripesof dark brown, or black, may 

 be seen on the sides of the body, three above the lateral line, and three or four beneath it. The 



