SAND DUNES AND SALT MARSHES 



summer the high tides float up the delicate 

 empty shells of the young horseshoes in hun- 

 dreds on the marsh, for, like all crabs, growth 

 is accomplished only by splitting and shed- 

 ding the outside skeleton or shell. From this 

 discarded cuticle emerges a soft-shelled and 

 helpless individual. In this state, however, 

 they are not often found, first, because the 

 stage is short, and secondly, because they re- 

 main concealed until they harden sufficiently 

 to brave the rough world. When in the usual 

 condition they are provided with a weapon, 

 w^hich, for a bare-footed man at least, is most 

 formidable. I refer to the long terminal 

 sharp-pointed spine or tail, w^hich they can 

 erect at will. The horseshoe is a fair swim- 

 mer and w^alker, and advances straight for- 

 ward, disdaining the indirect methods of true 

 crabs, and it burrows deep in the sand by 

 pushing its rounded front under the surface. 

 The beach flea, he of the large eyes, a plump, 

 clean, shrimp-like creature about half an inch 

 long, owes its name to its hopping powers 

 only,— for it does not bite the living but only 

 the dead. It is one of the most important 

 beach scavangers, and dwells in holes from 

 eight to ten inches deep near high-water mark. 



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