Radcliffe. — Sharks and Rays from N. C. 39 



bucklers or spines. As a rule, in the sharks the denticles 

 from a particular body region are very uniform in shape. 

 In many species this form appears to remain constant 

 through life, in others there is some modification with 

 age. Once we have learned the form and the variation, if 

 any, for a given species, these have an important classifi- 

 catory value. 



One of the questions frequently asked regarding the 

 sharks is that of whether they will attack a human being. 

 On this subject we have very little positive information. 



As an illustration of their ferocity I wish to relate an 

 incident that happened at Beaufort this summer. On 

 August 8, a small school of large tiger sharks (Galeocer- 

 do arcticus) appeared in the Fort Macon channel near 

 the Fisheries Laboratory, swimming around the Fisher- 

 ies Steamer "Fish Hawk." 



A baited shark hook thrown over the side was seized 

 by the largest of the school. The line offered little resist- 

 ance to this big fellow and he disappeared, taking bait 

 and hook with him. During the time that was required 

 to secure and bait another hook, the rest of the school 

 came up under the stern of the ship, showing no fear for 

 the men a few feet above them. Apparently they were 

 very hungry and prepared to grasp anything in the na- 

 ture of food that might fall to them. When the second 

 hook was thrown over it was seized by one of these. This 

 shark, which was 8 % feet in length was killed and 

 brought on deck. For the second time the hook was 

 thrown overboard and soon another specimen, slightly 

 over 10 feet in length, was hanging from the boom with 

 its head out of the water. On the third cast another, 

 9 feet 2 inches in length, was hooked. At this time a 

 shark, larger than any of those taken, swam up to the one 

 hanging from the boom and, raising his head partially 

 out of the water, seized the dead shark by the throat. As 

 he did so, Captain O'Brien began shooting at him with 

 a 32-caliber revolver, shooting as rapidly as he could take 

 aim. The shots seemed only to infuriate the shark, and 

 he shook the dead one so viciously as to make it doubtful 



