44 NEW YORK STATE MUSEUM 



Body slender, moderately long, its greatest depth about one 

 eighth of the total length, and about three fourths of the 

 length of the head; caudal fin scarcely bent upward, its length 

 nearly one fifth of the total length; snout pointed, its length 

 equaling about one fourth of the length of the head; mouth 

 slightly arched, with a long, straight, deep, oblique groove on 

 each side, without labial folds. Teeth small, equal in both 

 jaws, their points turned aside so that the inner margins form 

 a cutting edge; spiracles well developed, just behind the eye; 

 eye large, oblong, its diameter two thirds of the length of the 

 snout; no nictitating membrane; gill openings narrow slits, in 

 front of the pectorals; first dorsal moderate, larger than the 

 second, far in advance of the postmedian ventrals, which are 

 in front of the small second dorsal; pectoral when extended 

 reaches to below the first dorsal spine, its length contained 

 about seven times in the total, including caudal fin; ventral one 

 fourth as long as the head: 



Color dark slate or gray on upper parts, whitish below, numer- 

 ous white spots on the back, becoming faint or obsolete with 

 age. The spined dogfish reaches a length of 3^ feet and the 

 weight of 20 pounds. It inhabits both coasts of the Atlantic 

 and is recorded also from Cuba. It is found in Gravesend bay, 

 Long Island, only in October, and young examples have been 

 taken at Southampton in the same month. The species is 

 common in summer and fall on the fishing banks off the New 

 Jersey coast. It is not hardy in captivity. 



At Woods Hole Mass., according to Dr Smith, it is less abun- 

 dant than formerly, and was comparatively scarce in 1897. When 

 the fish fertilizer factory was established at Woods Hole, this 

 was the principal fish utilized in the manufacture of oil and 

 guano; later, the scarcity or irregularity of the supply necessi- 

 tated the use of menhaden. 



When the horned dogfish first comes, in May, it feeds largely 

 on ctenophores. 



In Massachusetts bay the species arrives in June and remains 

 only a few days, but returns again in September and stays till 



