until they become full grown in the megalops state. Say men- 

 tions that his specimens were found cast upon the beach by the 

 refluent tide and "appeared desirous to protect themselves, by 

 burrowing in the sand, in order to wait the return of the tide," 

 but they were more likely awaiting the final change to the terres- 

 trial state. The tufts of peculiar hairs between the bases of the 

 second and third ambulatory legs, and in the adult connected 

 with the respiration, are present in the full grown megalops, and 

 are undoubtedly provided to fit the animal for its terrestrial ex- 

 istence as soon as it is thrown upon the shore. The young in the 

 megalops stage occur on the shore of Long Island, in August, and 

 perhaps earlier. At Fire Island Beach, in 1870, no specimens of 

 Ocypoda were discovered till the last of August, and those first 

 found were the smallest ones obtained ; by the middle of Septem- 

 ber, however, they were common on the outer beach, and many of 

 them were twice as large as those first obtained. Although care- 

 ful search was made along the beach for several miles, not a speci- 

 men of the adult or half-grown crab could be found. Every indi- 

 vidual there had evidently landed and developed during the sea- 

 son. Probably all those living the year before had perished 

 during the winter, and it is possible that this species never sur- 

 vives long enough to attain its full growth so far north. 



New Haven, June 1, 1873. 



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