366 



SYNOPSIS OF THE CYPRINIDJE OP PENNSYLVANIA. 



The alimentary canal in the above species is nearly as long or as long as the head and 



body. 



CERATICHTHYS MICROPOCON, Cope, 



Proc. Acad., Phila., 1864, 277. 



The appearance of the head of this fish is that of a Hypsilepis rather 

 than of a chub, and the difficulty of discerning the minute barbels increases 

 the liability to err in determining its affinities. 



Mouth slightly oblique ; angle opposite anterior border of orbit. Latter enters 31 times in 

 length of head, which is measured 32 times in length from muzzle to base of tail. The greatest depth is measured 

 41 times in the same distance. Head broad, muzzle obtuse, profile rounded descending. Caudal peduncle long. 

 Scales as in C. biguttatus, § 40. Teeth 4 — 4, without masticatory surface, the posterior considerably hooked. 

 Length, from origin of tail to anterior base of dorsal equal from dorsal to posterior nostril. Rays, J). 1.8; C 1!) ; 

 A. 1.7 j V. 8; P. 18. Above pale yellowish-brown, with brown vertebral band; a broad brown shade from end 

 of muzzle to base of tail ; below pale yellowish. Length, 3 in. 6 lin. 



Renewed examination confirms the normal distinctness of this singular fish. Were we 

 disposed to adopt the hybridization hypothesis of Von Siebold, this species might be as- 

 cribed to the parentage of Ceratichthys biguttatus and Hypsilepis cornutus. On this 

 question there are, however, no affirmative evidences extant. 



1 only know this species from a specimen sent me by my friend, Jacob Stauffer, of Lan- 

 caster. He took it in the Concstoga, a tributary of the Susquehanna. Whether it occurs 

 in any of the other hydrographic basins is not yet known. 



CERATICHTHYS BIGUTTATUS, ffirthnd. 



Boston Journ. Nat. Hist., iii, 1840, 344. Ceratichihys, Baird, Girard, Proc. Acad. 

 Phila., 1856, 213. 



The largest specimen of this species before me measures six and a half inches long. 



Habitat. Lake Superior; specimens from the Montreal lliver, Keweenaw Pt., Lake Superior, from a fine col- 

 lection made for the Academy, by our member, Dr. J. II. Slack. This species is quite peculiar in physiognomy 

 in the genus. The Gobio plumbcus, Agass., has a much shorter head (one-fourth length) and smaller eye, and 

 resembles more the Semotilus type. The stomach was filled with homopterous insects. 



