LITHODES. 69 



cimen in Billiugsgate Market, amongst oysters from AYhit- 

 stable in Essex, in 1825. Mr. Ingall found it at Beachy 

 Head, in Sussex, in 1848. Dr. Lukis told me, in 1856, 

 that this species is taken in fine condition among the Chan- 

 nel Islands. 



Eam. LITHODIJDjE, Leach. 

 Carapace generally very much covered with spines, and 

 ending in a longish beak. Inner antennae long and ex- 

 posed ; the second, third, and fourth pairs of legs very long ; 

 the fifth pair very short, and not used in walking. 



Gen. 24. LITHODES, Latr. 



Carapace triangular, covered with spines. Beak very 

 long ; fifth joint of outer jaw-feet oblong, and seldom wider 

 than the fourth. Carapace with its last ring not united in 

 the same piece with the preceding, but free, and even mov- 

 able. Hind legs very small, and folded back into the interior 

 of the branchial cavities. 



There are five or six species of this distinct genus now 

 known to naturalists. Mr. Dana* describes one of these, 

 * Crustacea of the United States Exploring Expedition, i. p. 428. 



