VELVET-CRAB, MASKED-CRAB. 197 



dredging, offers a form of body and limbs strikingly dis- 

 similar to those of the Spider-Crabs, and a corresponding 

 difference of habits. In these the body is generally very 

 broad in proportion to its length, and wider in front 

 than it is behind. The front margin of the shell has a 

 rounded outline, but is more or less toothed ; the ros- 

 trum is broad, and but little prominent, and the eyes 

 are widely separated. But the most striking character 

 of the family is found in the hinder pair of legs, which 

 are converted into oars, and used by the animal in swim- 

 ming. The habits of these Crabs are much more active 

 than those of the Spiders, their limbs much stronger, 

 and they are all armed with a peculiarly effective pair 

 of stout pincers. The Velvet-Crab (Portunus puber) is 

 a well-known species of this family, several of which 

 are among the most beautiful of the British Crabs. The 

 Velvet-Crab is so named from its coat, the whole sur- 

 face of the shell, and of the legs, except some polished 

 longitudinal ridges, being covered with a short pile of 

 soft hairs. The colours of the living animal are a beau- 

 tiful compound of reddish-brown and blue ; but they 

 soon fade after death. Some remarkable forms of body 

 are found in the genus Ebalia, Crabs of small size, of 

 which there are three British species. The carapace in 

 these is rhomboidal, the lateral angles being much pro- 

 duced. It is marked with elevations and depressions, so 

 arranged as to represent a more or less perfectly formed 

 face. But the most natural resemblance to a human 

 face is found in the markings of the shell of Corystes 

 cassivelaunus, called from this peculiarity the Masked- 

 Crab by Professor Bell. It is the Cancer personatus of 



