36 VERTEBRATE ANIMALS OF THE UNITED STATES 



small; branchiostegals 6; pseudobranchiae large; eyelid adipose; anal 

 fin very long and low; tail forked: i genus. 



Dorosoma Rafinesque. With the characters of the family: 10 

 species of mud-feeding fishes, in warm seas and rivers; i in the United 

 States. 



D. cepedianum (LeSueur). Gizzard shad; mud shad. Length 

 375 mm.; head 4.3; depth 2.5; color silvery, being bluish above; rays 

 of dorsal fin 12, its posterior ray very long and extending back half 

 the distance to the tail; rays of anal fin 31; scales 56-23; stomach Hke 

 a fowl's gizzard: Cape Cod to Mexico, in the sea and ascending the 

 rivers; Mississippi Valley; introduced into Lakes Erie and Michigan 

 and in ponds from New Jersey to Texas; common; of little food value. 



Family 3. Clupeidae. — Herring; shad. Body oblong or elongate, 

 covered with cycloid scales; mouth large and terminal; teeth feeble 

 or wanting; maxillaries formed of 2 or 3 pieces and forming side of 

 upper jaw; pseudobranchiae 6 to 15; no lateral line; branchiostegals 

 6 to 15; tail forked: about 30 genera and 150 species, mostly marine, 

 inhabiting all seas; a few species live in fresh water and several marine 

 ones enter streams to spawn. A number of marine species, such as 

 the common herring, Clupea harengus L., the ale wife, Pomolohus 

 pseudoharengus (Wilson), the shad, Alosa sapidissima (Wil.), the 

 European sardine Clupanodon pilchardus (Walbaum) and the men- 

 haden, Brevoortia tyranniis (Latrobe), swim in large, often immense, 

 schools, and are very important food fish. 



Key to the Fresh Water Genera of Clupeidae 



ai Jaws with teeth i. Pomolohus. 



a2 Jaws toothless 2. Alosa. 



I. Pomolobus Rafinesque. Body eliptical, compressed; scales 

 cycloid; teeth feeble: many species, mostly in northern seas. 



P. chrysochloris Raf. Skipjack. Length 375 mm.; head 3.75; depth 

 3.75; color brilliant blue above; sides silvery, with golden reflections; 

 rays of dorsal fin 16; anal 18; scales 52; lower jaw projecting: Mis- 

 sissippi Valley and Gulf of Mexico; common in the larger streams; 

 introduced into Lake Erie and Michigan; of no food value. 



P. pseudoharengus (Wilson). Alewife. Length 375 mm.; head 4.6; 

 depth 2)-y, color bluish above, with silvery sides; a small black spot 

 behind the opercle; rays of dorsal fin 16; anal 19; scales 50: Atlantic 

 Ocean, south to South Carolina, entering the streams to spawn; in 

 Lake Ontario and the lakes of central New York; very common. 



