384 



SYNOPSIS OF THE CYPIUNID/TC OP PENNSYLVANIA. 



to me. The scale formula and form of head in the H. hudsonius are quite different; 

 the appearance as well as details of the living fry of Hypsilepis cornutus and kentukiensis 

 from the same waters, is entirely distinct. In general the characters are most like those 

 of the last named ; leaving out of view the generic difference in the form of the scales, 

 specimens of nearly the same size may be distinguished as follows : 



II. kentukiensis. 



Dorsal outline continuous beyond dorsal fin; 



caudal peduncle deep. 

 Eye three and two-thirds times in head. 



.//. chalybaeus. 



Dorsal outline depressed beyond dorsal fin, 



forming slender caudal peduncle. 

 Eve three times in head. 



The coloration of the young kentukiensis is identical with that of the adult, and en- 

 tirely different from that of the present species. 



The Hybopsis chalybaeus is much less abundant than the II. procne ; I have not yet 

 seen it sold for aquaria, in which it would, however, be a greater ornament. The stomach 

 of a specimen opened, contained minute insect larvae. 



HYBOPSIS BIFRENATUS, Cape. 



This small species agrees in dentition, squamation, and radial formula} with the II. 

 procne, but differs in the deeper body, more oblique mouth, the almost absence of the 

 lateral line, and in coloration. Its affinities are really nearer the II. heterodon, from 

 which the points of the table will distinguish it ; while its general appearance is sur- 

 prisingly like the H. chalybaeus. 



Color above straw, the scales delicately brown-edged ; below impure white, with a narrow black line along base 

 of anal fin to caudal. Along each side from the caudal fin round the end of the muzzle, including the end of the 

 mandible, a shining black band, one and one-half scales in width. This is bordered above on the muzzle, forming 

 an arc from orbit to orbit by an orange band, which is strongly margined above by the brown of the top of the 

 front. Opercular and suborbital regions below the black band, pure silvery. 



Front convex between the orbits ; length of muzzle equal diameter of iris band and pupil, sometimes nearly 

 equal orbit. Iris colored in continuation 'of the lateral band. The lateral line rarely extends half way to the 

 dorsal fin, while the pores of the same may be observed at the bases of the scales for half the remaining length of 

 the animal. Length of the largest specimen, nineteen lines; breadth of muzzle at nares 1.5 lines. Radii of the 

 scales strong. 



I have examined carefully at least one hundred individuals of this species which I took 

 near the mouth of a stream which flows into the Schuylkill at Conshohocken, in company 

 with Hybopsis procne and Hypsilepis kentukiensis. Large numbers of the three were 

 taken, from young of six lines in length to nearly adult age of the last mentioned. The 



