NOTES ON SOME NORTH CAROLINA 

 SHARKS AND RAYS 



By Lewis Radcliffe, 

 U. S. Bureau of Fisheries, Washington, D. C. 



During the course of preparation of a report on the 

 sharks and rays found in the vicinity of Beaufort, N. C, 

 the difficulties of the field man who secures one of these 

 monsters of the sea to determine its identity, have fre- 

 quently been felt. One cannot carry a 12 to 40-foot shark 

 with ease to his library or workshop, nor does he, as a 

 rule, have his library with him. In the majority of cases 

 I have found that if the jaws and a portion of the skin 

 from below the dorsal fin are saved, these will afford suf- 

 ficient material for determining the identity of the spe- 

 cies. I hope the specimens which will be shown you, and 

 a few notes regarding them, may prove of interest. 



As you are aware, the teeth aid the mouth in seizing, 

 holding, cutting or crushing the various kinds of food 

 material. The diversity in form and arrangement of 

 these organs, developed according to the needs of the 

 particular species, is surprising. In the sand shark 

 (Carcharias taurus), the teeth are long and subulate, 

 well fitted for seizing and tearing to pieces smaller fishes. 

 It is said that the species is very voracious, that they 

 work together in schools and surround and attack schools 

 of other fish, even those imprisoned in the nets of the 

 fishermen. The teeth of the thresher shark (Vulpecula 

 marina) are similar in form. This species is also re- 

 ported to be very destructive to fish life, using its tail, 

 which is about as long as the rest of the body, to strike 

 and stun, or kill, the unfortunate members of the school 

 of fish who fail to get out of its reach. 



In many species of sharks, some or all of the teeth are 

 triangular, with or without serrate cutting edges. This 

 is true for the man-eater (Carcharodon carcharias), the 

 blue shark (Galeus glaucus), most of the species of the 

 genus Carcharhinus and others. In the hammer head 



