SYNOPSIS OF THE CYPRINIDJE OF PENNSYLVANIA. 



373 



dark below is a luminous line which does not attain the tail, which is very visible in the water, and from above 

 when wot and out of water. Sides from rosy to silver-white, the scales in adults blackish at bases. Anal, ventral, 

 and pectoral fins bright crimson in spring and summer, in males. Operculum rosy, head dark above. The males 

 in spring have the branchiostogal membranes and the chin bright crimson. 



Total average length 5 in. 7 lin. ; head 1 in. 1 lin. ; end muzzle to base anal 3 in. ; depth at dorsal 1 in. 4 lin. ; 

 at anal 11.5 lin. 



The above description is taken from an adult from the Conestoga, Lancaster County. 

 Many Susquehanna specimens exhibit a more elongate form of head and body than speci- 

 mens from the tributaries of the Delaware. They often differ from those of the Susque- 

 hanna in having a row of scales or two more below the lateral line. In Delaware speci- 

 mens the head is shorter than in the latter, not more so than in the former, but the depth 

 of the body is greater than in cither, entering in length to base of tail three and one-third 

 times ; in the others four and four and one-third times. The dorsal fin is a little more 

 anteriorly situated in the Delaware specimens, and there is a row of scales more below the 

 lateral line than in Susquehanna specimens. With typical specimens only, these might 

 be regarded as representing two species, and as such I have already alluded to them ; but 

 in the large number of individuals at my disposal, I find transitions in all the points. The 

 Delaware specimens more nearly resemble the H. cornutus, figured by Dr. Storer. 



This is one of the most widely distributed of our CyprinidtB, occurring from New Eng- 

 land through the Middle and Western States to beyond the Mississippi. In the waters of 

 the Susquehanna and Delaware basins it is, with the Argyrcus atronasus, the most abun- 

 dant species. It prefers clear waters and does not haunt rapids. 



The best figure of this, as well as of some of our other Cyprinidte, is given by Dr. 

 Storer in his excellent Monograph on the fishes of Massachusetts. 



HYPSILEPIS DIPL^EMIA, Raf. 



Leuciscus diphemia, Raf., Ichthyologia Ohicnsis, 50. Luxilus do., Kirtland, Bost. 

 Journ., N. It., 1845, 276. Tab. Plargyrus do., Girard, Proc. Acad., Phila., 1856. Hyp- 

 silepis do., Cope, 1. c, 1864. 



This species has somewhat the form, as it has the coloration and minute nuptial excrescences, of the species of 

 (jhnostomus; as in them the dorsal fin commences slightly behind above the origin of the ventrals ; its hinder 

 margin is opposite the origin of the anal, to which the ventrals attain. Anal elongate, its last ray horizontal, 

 outline behind, vertical concave. Dorsal elevated, rounded above, length of first articulated ray one-half from its 

 base to base of caudal. Radial formula D. 1.9 P. 12. V. 8. A. 1.1 1. 0. + 18 + . Dorsal outline elevated, superior 

 line of cranium scarcely arched, head rather compressed ; body rapidly narrowing to caudal peduncle at dorsal and 

 anal fins. Caudal expanded dot-ply eraarginate. 



