202 



NATURAL HISTORY. 



Land Crabs are very abundant in the Deccan ; they have been found on the table-lands at an 

 elevation of nearly 4,000 feet. But as they do not perform an annual migration to the sea for the 

 purpose of depositing their eggs, it seems highly probable that the Deccan species frequents the 

 margins of streams, and deposits its eggs in fresh water, in which case the nearest river would serve 

 the same purpose ; for the young must undergo their metamorphosis either in the water or within the 



egg itself before it is 

 hatched, several authentic 

 instances of which are 

 known. ' Another form, 

 the Calling Crab (Gela- 

 sitmis), is a great bur- 

 rower, inhabiting the 

 coasts of Brazil, ifec. He 

 has one large hand and 

 a small one, and from 

 the way in. which he is 

 compelled to run in order 

 not to overbalance himself 

 with his big claw raised 

 above his head, as if 

 beckoning, he has ob- 

 tained the name of Calling 

 Crab. This powerful hand 

 is used in throwing the 

 earth and sand out of its 

 burrow when digging, 

 which he does most 

 vigorously to a distance 

 of a foot or more from 

 the hole = 



The Ocypoda, or 



Horseman Crab, from Rio, is another interesting species of Land Crab. It makes a loud grating 

 sound by means of a series of small ridges on the inner surface of the hand against the pro- 

 minent edge of the second joint of the same pair of legs. There is really no voice organ (truly 

 so called) in any of the Invertebrata. Mosquitoes " sing," Bees " hum," Crickets " chirp," 

 and Beetles " drone ; " but these are all mechanical noises, made by movements of wings or 

 legs, not with such a contrivance as the human throat. Most of these sounds are produced by an 

 arrangement similar to that of the fiddle-bow drawn across the strings of the fiddle, whilst many of 

 the harsher sounds have been aptly compared to the noise produced by street-boys scraping a stick 

 along a row of iron railings. 



The Pea Crab (Pinnotheres) is an interesting genus, both on account of its diminutive size and 

 from its singular practice of making its habitation within the valves of living bivalve shells. The 

 writer has taken numbers of them alive from shells as small as Astarte and Cytherea 

 at Malaga. One species (Pinnotheres pisum, Fig. 18) is so common on the Irish coast, 

 that Mr. W. Thompson obtained fourteen of them, by opening eighteen of the larger or 

 Horse Mussel, dredged off the shore of County Down ; and in the common Cockle 

 at Youghal Mr. Ball found them so abundantly, that about nine out of every ten 

 Cockles contained a Crab. Two and even three Crabs are occasionally found in one THE UES PISUM. 

 Mussel, or in one Pinna. 



Pinnotheres veterum is the species found in the Mediterranean, whose history, mingled with 

 much fable, is recorded by some ancient authors. 



The ANOMOURA, or irregular-tailed Crabs, form the connecting link between the Crabs and 

 Lobsters, for, besides the Hermit Crabs proper, which are generally considered typical of the 



Fig. 17. VIOLET LAND CRAB OF JAMAICA. (Gecarcinus ruricola.") 



