FISHES OP NEW YORK 59 



teeth sometimes much enlarged, sometimes not much larger 

 than the outer teeth; tail long, whiplike, with a small dorsal 

 spine behind the dorsal fin which is at the base of the tail; 

 ventral fins oblong, truncated behind. 



33 Rhinoptera bonasus (Mitchill) 



Cow-nosed Ray 



Raja bonasus MITCHILL, Trans. Lit. & Phil. Soc. N. Y. I, 479, 1815. 

 Miinoptera qiiadriloba DE KAY, N. Y. Fauna, Fishes, 375, pi. 66, fig. 

 217, 1842; GUNTHER, Cat. Fish. Brit. Mus. VIII, 494, 1870; JORDAN & 

 GILBERT, Bull. 16, U. S. Nat Mus. 51, 1883. 



Rliinoptera bonasus JORDAN & EVERMANN, Bull. 47, U. S. Nat. Mus. 90, 1896; 

 SMITH, Bull. U. S. F. C. XVII, 90, 1898. 



The length of disk equals two thirds of its width; its anterior 

 borders almost straight, posterior undulated; pectorals acutely 

 produced; muzzle deeply emarginate; mouth wide; nostrils mid- 

 way between mouth and tip of snout; spiracles large, longer 

 than eye; teeth in seven rows in each jaw, the median teeth 

 more than four times as broad as long, the others gradually 

 diminishing in size outward; tail very slender, as long as the 

 body; a small dorsal fin at base of tail and a slender, serrate 

 spine behind it; skin smooth except a few protuberances on the 

 top of the head. Color olive brown above; beneath white. Cape 

 Cod to Forida; not rare. 



This species is now rarely seen in Gravesend bay, where it 

 was at one time very common in the autumn. When Mitchill 

 wrote of the fishes of New York (1815) he stated that the cow- 

 nosed ray visits the coast, usually about September, in numer- 

 ous shoals, entering the bay and ranging very extensively over 

 the flats where the soft clam lives. 



These shellfish he is supposed to devour; for a shoal of cow- 

 noses roots up the salt water flats as completely as a drove of 

 hogs would do. I have seen the water in violent agitation when 

 these fishes were at work in the bottom. They render it so 

 muddy that they are concealed from sight. Frequently, how- 

 ever, they rise to the top and may be distinctly observed. I 

 have seen them swim near the surface in clear water. They then 

 support and propel themselves in their element by their large 

 flaps as a crow or other bird, with slowly moving wings, passes 

 through the air. They may be said to fly rather than to swim. 

 A full grown individual weighs about 100 pounds. 



