THE FISHES OF NEW JERSEY. 67 
Genus Souatus Linnezeus. 
The Spiny Dog Sharks. 
Squalus acanthias Linneus. 
Spiny Dog Fish. Cod Shark. Cod Fish Shark. Thorn Back 
Shark. 
Head 5%4; depth about 714; snout 2% in head; width of 
mouth 3; interorbital space 273; front edge of pectoral 1%; 

Spiny Dog Shark. Squalus acanthias Linneus. 
length of caudal peduncle 134; upper caudal lobe 4% in rest of 
body. Body long and slender. A pit at root of caudal above. 
Head depressed, elongately triangular when viewed above. Eye 
elongate, a trifle anterior. Mouth little curved. Teeth simple. 
Nostrils midway in snout below. Internasal space a little less 
than space between tip of snout and nostrils. First dorsal mid- 
way between pectoral and ventral. Second dorsal smaller, nearer 
caudal than first dorsal. Caudal with lower lobe rounded, half 
length of upper. Pectoral small, not reaching first dorsal, and 
greatest width a trifle more than half its length. Ventral blunt. 
