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SYNOPSIS OF THE CYPRINID/E OP PENNSYLVANIA. 



The family of the Cyprinicte is thus denned : 



Pharyngeal bones short, with an external ala, supporting a short series of not more than seven teeth, which have 

 cylindric or sub-cylindric shanks. Mouth bounded above by the prcniaxillary only, not surrounded with fleshy 

 lips. Dorsal fin with an osseous spine.* 



My object is to present here a brief outline of characteristics of the species found in the 

 waters of our State, for the benefit of students, since the present state of the literature of 

 the subject renders the study of them very laborious. 



Three memoirs comprise most of our knowledge of the subject, viz., two by Prof. Agas- 

 si/, in Silliman's Journal, 1854-5, On the Fishes of the Tennessee Iliver, and the Cypri- 

 nidcC of the Pacific Slope of North America, and one much more extended by Girard, in 

 Proceedings Acad. Nat. Sciences, Phila., 1856, on the Cyprinidee of the Mississippi Valley. 

 Prof. Kirtland's Fishes of Ohio (Boston Journ. Nat. Hist.), and Storer's Synopsis of Fishes 

 of North America (Trans. Americ. Academy), are also necessary to a comprehension of 

 the subject. 



Our genera as at present understood, are fifteen in number ; they express the natural 

 relations of twenty-eight species. These arc mostly of small size, and bear so close a 

 resemblance to each other as to be confounded by ordinary observers during the seasons 

 when not in their nuptial dress. Then indeed the brilliancy of their coloring attracts the 

 most indifferent, and they arc caught to be admired in aquaria ; but they only fade on re- 

 moval from their native haunts. The gorgeous crimson of the Argyrci, the Chrosomi, 

 and the Clinostomi, are in no wise inferior to the tints of the boasted trout in his bright- 

 est array, and the admired gold-fish does not gain by the comparison. A few species 

 attain a moderate size ; the Stilbe americana and Semotilus corporalis occur of two lb. 

 weight, and the Semotilus rhotheus rarely reaches four. 



The Argyrei, the Chrosomi, and the Clinostomi prefer the clearest and most sparkling 

 rivulets, the home of the trout, whose rapid movements and bright tints they repeat ; 

 they occur everywhere, in close parties or little shoals. Some of the Semotili are fish of 

 much vigor of movement, and prefer the rapid waters of the larger creeks ; others are less 



* The following are the characters given by Prof. Gill (1. c), for this family: 



"The body is oblong or moderately elongated, compressed or sub-cylindrical, and covered with scales of various 

 sizes. 



"The barbels vary in number from two to four, and in numerous genera are even entirely absent. The pecto- 

 ral fins have broad vertical bases inserted in the usual manner on the sides above the breast. They have each a 

 simple ray. The dorsal and anal fins are either with or without spines, which themselves arc either simple or 

 dentatcd. The pharyngeal bones have normally one constant row of normally five teeth, occasionally four, and 

 often one or two supplementary rows of from one to three smaller tooth. The branchial apertures are of moderate 

 size, and separated from each other by an isthmus of little or moderate width." 



