Chap. 1Y. 



OECHESTIA DARWmil. 



25 



(fig. 7) lives in marshy places in the vicinity of the sea, 

 under decaying leaves, in the loose earth which the 

 Marsh Crabs (Gelasimus, Sesarma, Cyelograpsus, &c.) 



throw up around the entrance to their burrows, and 

 even under dry cow-dung and horse-dung. If this 

 species removes to a greater distance from the shore 

 than the majority of its congeners (although some of 

 them advance very far into the land and even upon 

 mountains of a thousand feet in height, such as 0. 

 tahitensis, telluris, and syhieola), its male differs still 

 more from all known species by the powerful chelae of 

 the second pair of feet. Orchestia grtjiohus, from the 

 sandy coast of Mönchgut, alone presents a somewhat 

 similar structure, but in a far less degree ; elsewhere 

 the form of the hand usual in the Amphipoda occurs. 

 Now there is a considerable difference between the 

 males of this species, especially in the structure of these 

 chelge — a difference so great that we can scarcely find a 

 parallel to it elsewhere between two species of the 

 genus— and yet, as in Tanais, we do not meet with a 



- Fig. 7. Orchestia Darwinii, n. sp. male. 



