GOULD MITHEACITES VECTENSIS. 



237 



Description of a New Fossil Crustacean from the Lower Greensand. 

 By Charles Gould, Esq., B.A., of the Geological Survey of Great 

 Britain. 



[Communicated by Prof. Huxley, F.E.S., F.G.S.] 



(Eead June 23, 1858.) 



I regard the Crustacean which I am about to describe with peculiar 

 interest, on account of its belonging to that group of the Brachyura 

 which comprehends the highest forms of the class, and of which 

 hitherto but one species (Mithracia libinoides, Bell*) has been de- 

 scribed as occurring in the fossil state in Great Britain. 



At present I am only aware of the existence of two specimens of 

 the species which I shall here describe, — one in the collection at the 

 British Museum, the other in that of the Geological Survey of Great 

 Britain ; both are from the Lower Greensand of Atherfield in the 

 Isle of "Wight, and in each the carapace only is preserved. It is 

 from an examination of these specimens that I have taken the fol- 

 lowing characters. 



Figs. 1, 2, 3. — Mithracites Vectensis, natural size. 



Fig. 1. 



Carapace, viewed from above. 

 Fig. 2. Fig. 3. 



Front view of the Carapace. Side view of the Carapace, in outline. 



Mithracites Yectensis, nov. gen. et spec. 



Carapace : arched in front, somewhat depressed behind, rotun- 

 date ; length slightly exceeding the breadth, which is greatest at the 



^ Monograph Fossil Malacostr. Crust. Great Britain, Part I. Crustacea of the 

 London Clay. (Pal^ontograph. Soc.) 1858, p. 9, pi. 5. figs. 10-12. 



s2 



