90 A HISTORY OF RECENT CRUSTACEA 



is frequently found in great numbers, either running 

 actively about over the sand, or peering cautiously from 

 their holes, which are often thickly scattered over con- 

 siderable areas. These holes are mostly from half an inch 

 to an inch in diameter, and a foot or more in depth, the 

 upper part nearly perpendicular, becoming horizontal 

 below, with a chamber at the end. Mr. Smith, by lying 

 perfectly still for some time on the sand, succeeded in 

 witnessing their mode of digging. In doing this they dug up 

 pellets of moist sand, which they carry under the three 

 anterior ambulatory legs that are on the rear side, climb- 

 ing out of their burrows by means of the legs of the side 

 in front, aided by the posterior leg of the other side. 

 After arriving at the mouth of their burrows and taking 

 a cautious survey of the landscape, they run quickly to 

 the distance often of four or five feet from the burrow 

 before dropping their load, using the same legs as before 

 and carrying the dirt in "the same manner. They then 

 take another careful sun>-ey of the surroundings, run nimbly 

 back to the hole, and after again turning their pedunculated 

 eyes in every direction, suddenly disappear, soon to reappear 

 with another load. They work in this way both in the 

 night and in the brightest sunshine, whenever the tide is 

 out and the weather is suitable. In coming out or going 

 into their burrows either side may go in advance, but the 

 male more commonly comes out with the large claw for- 

 ward. According to Mr. Smith's observations this species 

 is a vegetarian, feeding upon the minute algse which grow 

 upon the moist sand. In feeding, the males use only the 

 small claw with which they pick up the bits of algae very 

 daintily ; the females use indifferently either of their small 

 claws for this purpose. They always swallow more or less 

 sand with their food. Mr. Smith also saw these crabs 

 engaged in scraping up the surface of the sand where 

 covered with their favourite algae, which they formed into 

 pellets and carried into their holes, in the same way that 

 they bring sand out, doubtless stowing it until needed for 

 food, for he often found large quantities stored in the 

 terminal chamber.' 



