DECAPODA. 



211 



approach to Its future permanent form, the eyes become raised on 

 stalks the claws and feet begin to make their appearance, but the 

 tad stiU remams hke tliat of a lobster, and is used by the voun- 

 crab to swim about merrily in the water. It is uot until the nexT 



Fic, 



161.— SECOND ^TAGE OF SHOKE-CKAB. 



moult, when the little creature measures about one-elglith of an inch 

 m diameter, that the mature form is completely developed. The 

 facdity with whicli these crustaceans ca«t off their legs, and even 

 their heavy claws when they have bteu wounded, is a most remark- 

 able feature in their economy. Without the least appearance of 

 pain, they continue to run about upon their remaining legs, and won- 



stumn rff ^ !f' T"'^ *f '? ^ ^'^^ ^^^^ ^^^^'^ o^^t of the old 

 stump, and takes the place of the original member. When the old 



llrZu^^^I^t ',{" ^f ^/?™«' '-i"^! ^-emains until the anunal casts 

 Its shell. Alter the she 1 is thus cast, a protuberance in the centre 

 ot the scar suddenly enlarges, and under it may be seen a small 

 claw, doubled on itself beneath the membrane of the stump Tlds 

 remains m a soft state until the crab again casts its shell, wiien the 

 new claw is set at liberty, straightened out. and becomes hard and 

 calcareous, like other pavts of the body. 



.J^^n ^'^^"^ °'' ^^^^'' ^^^^' (Ocypoda)* found on the coasts of Svria 

 and Barbary, run so quickly that a man on horseback is said not to 

 be able to overtake them. The West Indian species dig holes three 

 lp.v .1 ^^^^?^^P' immediately above high-water mark, and only 

 leave them after dusk. ^ 



okys, swift : irovs, iroBos, pons, podos, a foot 



