PREFACE 



In 19^^^ the U. S. Navy produced a newly developed shark repel- 

 lent for standard issue in survival kits. It soon became apparent, 

 however, that the greatest value of this repellent was as a morale 

 booster for survivors in the water, inasmuch as its efficacy as 

 protection against sharks was questionable. To this day the development 

 of an effective antishark device remains a pressing problem to the 

 Navy. At a recent symposium on sharks (1958), scientists agreed that 

 although the development of a deterrent was essential, the solution 

 of the problem was hampered by a lack of fundamental knowledge con- 

 cerning shark biology. A committee on research recommendations which 

 met during the syoiposium stressed the need for more intensive research 

 on identification and classification, distribution, abundance, 

 behavior, and ecology of sharks, as well as continued efforts to 

 develop a satisfactory repellent. 



All three genera in the family Lamnidae eire considered to be 

 potentially dangerous to man. Of the three. Car char odon and Isurus 

 have been involved in authenticated attacks on maji. 



Since the publication in 19^8 of Bigelow and Schroeder's 

 invaluable treatise on sharks of the western North Atlantic, some new 

 data have become available concerning the lamnid sharks. The present 

 report is intended as a summary of available data on some aspects of 

 their biology. 



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