VI. Description of Chiasognathus Grantii, a new 

 Lucanideous Insect forming the type of an unde- 

 scribed Genus, together with some brief Remarks 

 upon its Structure and Affinities. In a Letter ad- 

 dressed to one of the Secretaries. 



By J. F STEPHENS, Esq. F.L.S. 



[Read May 16, 1831.] 



My Dear Henslow, 



The magnificent Beetle submitted by you to my 

 inspection proves to be, as I anticipated, not only perfectly novel 

 to science as a species, but forms the type of a genus as in- 

 teresting from its structure, as it is remarkable for its splendour 

 and colouring. I shall therefore very briefly notice some of its 

 peculiarities, though I cannot but regret that from the circum- 

 stance of my attention having been chiefly directed to indigenous 

 entomology, the task should have devolved upon one so little 

 conversant with exotic forms, and more especially as Great 

 Britain is remarkably deficient in the group to which the present 

 insect belongs. 



The Lucanidae, to which family Chiasognathus appertains, 

 are distinguished amongst other characters by the extraordinary 

 developement of the mandibles in the males, which in the 

 common Stag-beetle rarely exceed half the length of the body, 



Vol. IV. Part II. Dn 



