TORTOISE CRAB. C'tmaro C 



very few examples have been recorded where a limb has been lost and replaced, but such 

 phenomena are extremely rare, and can only be looked upon as variations from the usual 

 system. 



THE faculty of avoiding danger by closing all the joints of the limbs and merging them 

 as far as possible under the carapace, is carried to a wonderful extent in the TOKTOISE- 

 CRAB, a crustacean that derives its popular title from its general similitude to the reptile from 

 which it derives its name. There are, indeed, many of the tortoise tribe which are not able 

 to enclose themselves nearly so perfectly as does this crab, and excepting the box-tortoise, 

 there is perhaps none that exceeds it in the very perfect concealment of all vestige of 

 their limbs. The carapace is wide, flattened at the edges, and dome-like in shape, so as to 

 afford a perfect cover to the limbs. Owing to the manner in which these crabs conceal 

 their limbs, Cuvier called them by the appropriate name of Cryptopods, or Hidden Feet. 

 In all of these creatures the carapace is domed or vaulted, so as to form a shelter for the 

 legs, while in the typical genus the claw-feet are very large and compressed, with a 

 decided upper edge which is notched or toothed so as to form a crest. The French know 

 these crabs by various names, such as Migranes, Coqs de mer, and Crabes honteux. 



The claws are broad, flattish, notched at the edge, and scooped in a peculiar fashion, 

 so that when folded over the body they exactly fit to the shell, as if they were part of the 

 same piece. Two sides of this species are given in order to show the crab in its upper 

 and under aspects. The Tortoise-crab is a native of the Mauritius. 



IN the family of the Leucosiidse, the carapace is more or less rounded, and projects 

 somewhat in front. 



The larger figure on the accompanying illustration represents the UEANIA-CEAB, an 

 example of the typical genus. It has a smooth carapace with rounded edges, and the 

 claw limbs are very large and powerful in proportion to the size of the body. On their 

 edges they are covered with rounded tubercles, and one or two of these projections are 

 scattered upon the surface of several joints. In all these crabs, the apertures through 

 which water passes to cover the gills are in the form of canals. One curious characteristic 

 of these crustaceans is that the external antennae are very small indeed, and are inserted 



