FISHES OF PENNSYLVANIA. 63 

pounds contains about 25, 000 eggs on the average, but as many as 60,- 
000 have been obtained from a six-pound fish and 100,000 were obtained 
from a single female on the Potomac. There is great mortality among 
the shad after spawning. Dead fish of both sexes are frequently seen 
floating in the water in the late months of summer. 
Genus BREVOORTIA GILL. 
81. Brevoortia tyrannus (Larroszr. ) 
The Menhaden. 
The menhaden is a fish of the herring family. The exposed surfaces of its scales 
are very narrow and deep. The body is similar in shape to that of the shad, the 
depth one-third of length, without caudal, and somewhat greater than the length of 
the head. The mouth is large; the jaws are toothless. The upper jaw extends to 
below the hind margin of the eye. The eye is about as long as the snout, one-fifth 
length of head. The fins are small, the pectoral not much more than one-half the 
length of head and twice as long as the ventral. The dorsal base is equal in 
length to the pectoral; longest dorsal ray more than twice as long as the last ray and 
about two-fifths length of head. The anal rays are shorter than those of the dor- 
sal; length of anal base little more than one-half length of head. The origin of the 
dorsal is about midway between tip of snout and end of middle caudal rays. The 
sides and fins are silvery, yellowish, the upper parts bluish. Behind the head there 
is a large dark spot, larger than the pupil, followed by numerous smaller dark spots. 
The menhaden has received more than thirty common names, among 
which the one here employed is the best known and most suitable. In 
New Jersey it is frequently called bunker or moss bunker and in some 
other localities it is the bony fish. It is also called bugfish, because of 
a crustacean parasite which is found in the mouth. 
The menhaden reaches a length of fifteen inches or more. Its aver- 
age size is about one foot. It is found along our east coast from Maine 
to Florida, swimming in immense schools and fluctuating greatly in 
abundance. In certain localities its movements are affected chiefly by 
temperature. 
The use of the menhaden as a source of oil and a material for fertil- 
izers is so well known as scarcely to need mention here. As a food fish 
it is not esteemed in Pennsylvania and is seldom eaten in most locali- 
ties, although in other places it is considered a good food fish. Since 
the mackerel are becoming scarce, menhaden are often salted in barrels 
as a substitute for that fish. 
Genus DOROSOMA Rarrnesaue. 
82. Dorosoma cepedianum (Le Sueur). 
The Mud Shad. 
The genus Dorosoma has a herring-like body, with a short,and obtuse snout. The 
body is much compressed and is covered with moderately large, thin, cycloid scales. 
The head is scaleless, short and small; the eye large and provided with an adipose 
eyelid. The belly is compressed to an edge, which is armed with sharp serratures. 
