SYNOPSIS OF TDK CYPKINIDiE OF PENNSYLVANIA. 



389 



originate anterior to the dorsal, and do not extend to the anal. Base of anal more elongate than in rubellus, 

 equal depth of body at its fourth ray. D. I. 8. 0.+19 + . A. 2, 10. V. 8, P. 11, the four upper rays enlarged in 

 the spring, as in Argyreus, etc. Scales of upper surfaces covered with minute rugosities during the same season. 

 From origin of caudal to that of dorsal equal from latter to posterior border or middle of orbit. Length 2 in. 

 (J lin, 



Above yellowish-olive, the scales with punctulato margins; a median dorsal lino. A dark lateral band has a 

 distinct outline on the third row of scales above the lateral line, but vanishes in punctulations below; it is broader 

 and more distinct on the caudal peduncle. From its superior border a silver reflection extends over the white 

 abdomen. Sides of head silvery; chin, muzzle, lips, front, and vertex light vermilion during the breeding season. 

 Ihc bases of the fins, except the caudal, are similarly colored at this season. The pharyngeal teeth are but little 

 hooked; in three specimens, 2.4—4.1, and in two, 2.4—4.2. 



As may be supposed, this is an elegant little creature. It is found in considerable 

 abundance in the Kiskiminitas River, and no doubt in other tributaries of the Alleghany, 

 though I have only seen it from the former stream. Of its habits nothing is known. 



STI1.BE, Dekay. 



Nat. Hist. New York, 1842, Gill, Canadian Naturalist, LSG5. Plargyrus, Rafinesque. 

 Ichthyologia Ohiensis, Putnam Bulletin Mus. Comp. Zoology, No. I. Luxilus, Raf, Gi- 

 rard, Broc. A. N. S. Bhila., 1856. 



This form is readily distinguished externally by the elevation and compression of the 

 body and length of anal fin ; the head is small, and the mouth oblique and superior or 

 terminal. The ventral fins originate further in advance of the line of the dorsal than 

 usual ; the isthmus is moderate. 



STILBE AMERICANA, Linnaeus. 



Oyprinus americanus, Syst. Nat., 17(5(>. Oyprinus chrysoleucus, Mitchell, 181 

 mis versicolor, Dekay. Leucosomus americanus, Girard,* 1853. 



Scales rather large, (9 — )11 — 46 — 4, radii 4-6, much stronger than the numerous, close 

 concentric lines. Lateral line much deourved, not occupying even the middle of the 

 caudal peduncle. Head slightly concave between the orbits, contained five and one-fifth 

 times in length to end tail, occipital region very convex above preopereulum. Eye round, 

 three and two-thirds in length of head, once in muzzle; end of os maxillarc in line with 

 nares. Preorbital bone a trapezium higher than long. From origin of dorsal to median 

 base of caudal equal from former to opposite posterior margin of orbit; its base one and 



Abra- 



* Putnam Bulletin Mus. Comp. Zool., 1. c, includes Leuciscus boscii as synonymous with the present species, 

 but erroneously, as it is probably a Lavinia. Vid. Pr. A. N. Sei. I'hila., 1864, 283. 



