298 Papers from the Marine Biological Laboratory at Tortugas. 



account of its habit of plowing up mud banks and sand-bars with its snout in 

 its search for clams. He has often found it impossible to harpoon rays thus 

 occupied because of the clouded condition of the water. He says further: 



I have known beds, containing many bushels of planted clams, being attacked by 

 schools of these rays and every clam in them destroyed in less than a week; and on several 

 occasions I have had a pile containing a half bushel or more entirely destroyed during 

 a single tide by one or more of these rays. Clams appear to be almost if not entirely the 

 only food of this ray. I have opened more than 50 specimens and have carefully studied 

 the contents of the stomach and have never found that they contain any other food. I 

 am thoroughly convinced that the shell fish consumed by the American people every year 

 are as nothing to the countless thousands of bushels devoured by this ray and its relatives 

 every year. 



The muscular development of the jaws of this fish is truly wonderful. I have found 

 in these rays clams which with their shells on must have weighed more than 3 pounds and 

 to crack which a pressure of perhaps a thousand pounds would be required. And I have 

 found in the stomachs of these rays, on a number of occasions, more than a half gallon of 

 clams with the flesh of each clam less broken than the most expert human clam opener could 

 have turned it out; and the writer has often spread out these clams on a clean board and 

 carefully examined them and found that they were absolutely free from any pieces of broken 

 shells. 



OFFENSIVE AND DEFENSIVE HABITS. 



The spotted sting ray, so far as the writer knows, is an inoffensive fish. 

 The fisherman of Beaufort, notwithstanding the fact that they call this ray 

 the "devil-fish," do not have the fear of it that they do of the common sting 

 ray, Dasyatis say, which they familiarly designate "stinger." This is prob- 

 ably due to two facts. First the spotted ray does not, so far as my observa- 

 tion goes, oft'er so much resistance when taken; and secondly, its spine (or 

 spines), being situated far up on the root of the tail, is not nearly so danger- 

 ous as that of the stingaree, which is found about one-third to one-fourth 

 of the distance from the root to the extremity of the tail. Thus the ordinary' 

 sting ray can and not infrequently does inflict a wound by lashing out with 

 its tail (I have seen one in the "bunt" of the seine thus drive its sting in the 

 sides of the boat and break off the tip), while, on the other hand, the spotted 

 sting ray, if the object be removed but a few inches from it, can only strike 

 by throwing its whole body. Wounds inflicted by the stingaree are not 

 uncommon and I am acquainted with several Beaufort fishermen who have 

 thus suffered, but the only person whom I know to have been wounded by 

 the spotted ray is Mr. Coles, whose experience will be referred to later. 



The commonly accepted idea among fishermen is that this and other 

 sting rays all have poisonous stings, and perfectly reliable men of my 

 acquaintance at Beaufort have described how they have been stung by 

 stingarees, Dasyatis say, and how the hand or foot swelled up and what 

 excruciating pain they suffered and how they were disabled for work for a 

 considerable time thereafter. But so far as I can find by dissection and 

 reading no poison gland is ever found in the spotted sting ray or in the 

 stingaree, though there is a groove on the dorsal side of the spines of both 

 rays extending from the point of insertion of the spine to near its tip. 



