12 



CALIFORNIA FISH AND GAME. 



spots, hut not always. The spots may bo clear cut and separated, or 

 blended and more or less run together. 



This is the .smallest of our sting rays, but its num])ers and activity 

 make it one of the most dreadt'd by bathers. It scarcely exceeds a foot 

 in length, and is found on the coast south of Point Concepcion and 

 southward to Panama. In sheltered bays on shallow sand or mud flats 

 it occurs in almost countless numbers. 



The Rat-Tailed Sting Ray (Dasyatis dipterura). 



This is known from other sting rays of California by its long whip- 

 like tail, longer than the rest of the body, and in addition the eyes are 

 on top of the head, not near the edge of the disk. There is no dorsal 

 or caudal fin, but the tail is provided with a long vertical fold of skin 

 above and below. The outline of the disk is somewhat circular, though 

 the front edges are nearly straight and meet at a slight angle at the 

 snout. The skin is very slightly rough to the touch, and large speci- 

 mens have a row of enlarged spines along the middle of the ])ack, and 

 a couple of spines at the shoulder. The color is plain bluish brown 

 without spots. 



This ray is found in southern California and is rather abundant in 

 San Diego Bay. It reaches a length of 6 feet. 



c-^^ 



Fig. 14. The rat-tailed sting ray Dasyatis dipterura. Young male. 



The Butterfly Sting Ray (Pteroplatea marmorata). 



This may be known from all other skates and rays b.y the great width 

 of the disk and the very short tail. It is very much wider than the 

 entire length of the body and tail. The tail is flattened and has a 

 slight fold of skin above and below, ])ut no dorsal or caudal fin is devel- 

 oped. The skin is perfectly smooth and no spines or prickles are 

 developed anywhere. The sting is very small or frequently absent. 

 It is dark brown in color and mottled with small light drab spots and 

 short irregular lines formed by spots running together. 



