64 FISHES OF PENNSYLVANIA. 
Mouth small, transverse; the lower jaw the shorter. Jaws toothless. The maxilla 
does not extend to the middle of the eve. Gill rakers numerous, moderately long 
and slender. Gill membranes deeply cleft and free from the isthmus. Pseudo- 
branchiz well developed. Lateral line wanting. The dorsal fin 1s placed nearly 
over the middle of the body, slightly behind the origin of the ventral. Its last ray 
is produced into along filament. The pectorals and ventrals are.rather long and 
each is provided with an appendage formed of several elongate overlapping acces- 
sory scales. The caudal is deeply forked; anal very long, its last rays low. The 
stomach is stout and short, resembling the gizzard ofa hen. The depth of the body 
is contained two and two-thirds times in the total without caudal, the length of the 
head four and one-third times. Eye longer than snout, one-fourth length of head. 
The third ray of the dorsal is two-thirds as long as the head, and the filamentous ray, 
nearly equals the head in length. Length of dorsal base about one-half that of head’ 
anal base two-sevenths of total length of body without tail, its longest ray two-thirds 
length of ventral or one-third that of head. Pectoral three-fourths as long as head. 
Lower caudal lobe longer than upper, its length equai to that of the head. 
D. iii, 10; A. ii, 31. Scales 56 to 64, about 20 in a transverse series. Scutesin front 
of ventrals 17, and from ventrals to vent 12. 
Upper parts bluish ; sides silvery, sometimes with golden reflections. In young 
individuals there is a large dark blotch on each side not far behind the head: this 
disappears with age. 
The mud shad, also known as gizzard shad, winter shad, stink snad, 
white-eyed shad, hickory shad, hairy back and thread herring, is found 
in brackish waters along the coast from New York southward to Mexico, 
ascending streams and frequently becoming land-locked in ponds. A 
variety of this fish is also common in the Ohio and Mississippi valleys, 
from whence it has spread through canals into Lakes Erie and Michigan. 
This fish grows to a length of fifteen inches and a weight of two pounds. 
It spawns in summer and its food consists of algz, confervee, desmids 
and diatoms. With its food it takes large quantities of mud from which 
it separates the organic substances after swallowing. This is a beauti: 
ful species, somewhat resembling the shad in general appearance and has 
been very successfully kept in the aquarium, where its bright colors and 
graceful movements make it attractive, but its flesh is soft, tasteless and 
seldom eaten when any better can be obtained. In most regions fisher- 
men consider it a great nuisance and throw away their entire catch. 
Negroes eat the mud shad from tributaries of the Chesapeake, and in 
Florida the fish has been utilized to some extent in making guano. 'The 
name gizzard shad alludes to-the form of the stomach, which is very 
much like that of a hen. 
Famity ARGENTINIDA (Tue Smetrs). 
Genus OSMERUS (Arrepr) Linyxus. 
83. Osmerus mordax (Mircuiy). 
The Smelt. (Figure 46.) 
The smelt has an elongate and somewhat compressed body, and a long, pointed 
head, with the lower jaw projecting. The mouth is large, the maxilla extending 
slightly behind the eye. Small teeth on the intermaxillaries and maxillaries 
and the front of the lower jaw. Posteriorily the teeth of the mandible are larger. 
The tongue is armed with a few large, fang-like teeth and there are widely set 
