THE CYPRINOIDS OF CENTRAL NEW JERSEY. 335 
Pharyngeal teeth 1,4—4,1; moderately hooked, and with a 
narrow masticatory surface, more noticeable on one specimen ex- 
amined than on the other. The single tooth of the series is in 
all respects similar to the others, but only half the size. Occasion- 
ally the series is 2,4—4,2, as in .Alburnellus rubrifrons Cope. 
Anterior ray of dorsal slightly posterior to-the insertion of the 
last rays of yentrals. The anterior ray equals in length the pos- 
terior margin (terminal) of the fin. Terminal ray slightly in ad- 
vance of the anterior ray of anal fin. Anal fin broad, the base 
equalling the length of the anterior ray. Terminal margin of the 
fin slightly concave in outline. The pectoral fins terminate at a 
distance of three scales’ width from the insertion of the ventrals. 
Terminal margin of the ventrals opposite fifth ray of the dorsal. 
Lateral line decurved from the upper angle of the opercular ap- 
paratus, and continues in a slightly oblique direction to some dis- 
tance beyond the dorsal fin, and not rising again opposite that fin 
and continuing straight to the caudal fin, as in Alburnus rubellus 
Agassiz. D.1-8;A.1-11. Scales 5-39-3. Total length, 34 
inches. Color, pale olive above, with minute black dots on the 
_ exposed edges of the scales. A bright silvery band three scales 
wide at the operculum, and narrowing to a width of one and one- 
half scales at the base of the caudal fin. Operculum and iris 
pure silvery. Belly white, but not with a metallic gloss. 
he specimens taken were collected late in August, and the 
colors noted while they were in an aquarium. At present they are 
rare, both in the river and its several tributaries, and we are con- 
fident that we have never seen them previous to last summer, al- 
though accustomed carefully to collect-and study our various small 
fishes for the past dozen years ; and from the fact of finding it only 
in the canal, which has an unobstructed outlet into the Raritan 
River, 25 miles east of the Delaware, it may be that the fish in 
question is properly a species belonging to that river. It was in 
. this stream that the following species was first met with, in 1870; 
and now, as will appear, it is a very abundant species in some of the 
Delaware tributaries ; probably derived from the Raritan River, 
through the communication opened by the canal referred to. 
15. Hybognathus osmerinus Cope. This very interesting species 
was discovered by the writer, associated with our common smelt 
or “frost fish” (Osmerus viridescens Mitchill) from the Raritan 
River, at New Brunswick, N. J. It was first described by Prof. 
