From Bullrlin of the Bureau of Fisheries, Vol. X.XXIV, 1014 

 SHARK SKIN UNDER THE MICROSCOPE 

 Th(^ skin of a shark has no scales, hul is rough like sand paper owing to numerous minute asperities called 

 " dermal denticles." These when viewed under the microscope are seen to be of various forms, each form character- 

 istic of the s|)<;(:ies of shark it is found uj)on. In his paper The Sharks and Bays of Beaufort, North Carolina, 

 Mr. Lewis HadelifTe has even made the denticles a criterion for separating closely related species. In the case of 

 the nurse shark (Oinglymoslonta cirraluni) the denticles are so large and strong that it is difficult to drive a harpoon 

 into the fish 

 350 



