FISHES OF PENNSYLVANIA. 35 
length of seven inches, and is highly prized as a food fish. This min- 
now takes the hook very freely early in the spring, when gravid females 
are extremely common. 
I have placed this as a variety of H. nuchalis in deference to the 
views of Dr. Jordan, although it appears to me sufficiently distinct to 
retain the name applied to it by Girard. It is highly probable that the 
silvery minnow which Prof. Cope describes in the report for 1879-80 is 
the variety just mentioned. It has been found in the Raritan by Dr. 
Abbott, in the spring, associated with the smelt, and Prof. Cope justly 
believes that it will be found in the Delaware. 
Genus PIMEPHALES Rartnesave. 
45. Pimephales promelas Rarinesquz. 
The Fat-head Minnow. 
The fat-head minnow has a short, deep and moderately thick body, and the head 
short with a very obtuse snout. The greatest depth of the body is equal to or 
slightly greater than length of head, and is contained from three and two-thirds to 
tour and one-fourth times in total length without caudal. The least depth of the 
caudal peduncle equals the length of the postorbital part of the head. The head 
forms about one-fourth of the total length to base of caudal; the width of the head 
equals two-thirds of its length. The eye is as long as the snout and two-ninths as 
long as the head. The mouth is very small, terminal, slightly oblique, the maxilla 
not reaching vertical through hinder nostril. ‘The dorsal origin is above, and the 
ventral origin below the twenty-first scale of the lateral line. The dorsal base is 
two-thirds as long as the head ; the first ray is about as long as the eye, and the long- 
est as long as the head without the snout. The ventral reaches a little beyond the 
anal origin ; its length equal to dorsal base. The anal base equals nearly one-half 
length of head, and the longest ray is as long as the dorsal base. The caudal is mod- 
erate and not deeply forked. The lateral line is continuous on about twenty to 
twenty-eight scales, and in one specimen continued with interruptions almost to the 
caudal base. D.i, 8; A. i,7; V.8; P. 18; scales, 9-45 to 49-6; teeth, 4-4. Length 
of specimens described, three inches. Color in spirits light brown, top and sides of 
head darker. A broad dark band on the base of the dorsal, most distinct anteriorly 
and sometimes absent behind. Males in spring are dusky, with black head, and 
the snout and chin with numerous coarse tubercles. 
The fat-head or black-head is an inhabitant of the Ohio valley and the 
Great Lake region west to Dakota and southwest to Texas. It is com- 
mon in sluggish brooks, and instances have been known of its distribu- 
tion by the action of cyclones. In Pennsylvania it is common in tribu- 
taries of the Ohio. 
The fat-head grows to a length of two and one-half inches. The 
sexes differ in color, the females being olivaceous, while the males are 
dusky, and in the spring have the head black and the snout covered 
with numerous large tubercles. The species has no value as food, but 
it is an interesting one for the aquarium. Its food consists of mud and 
algwe, and it seems to prefer a muddy bottom. 
