the Coleopterous Genus Diphucephala. ^17 



As regards sculpture, the thorax is always furnished with a dorsal 

 channel more or less distinct ; this is a simple groove in all the 

 species excepting D. aurulenta and j^ftrvula, in which it is very 

 broad, and divided on the basal half of the thorax by a longitudinal 

 elevated smooth ridge ; or we may describe the thorax of these spe- 

 cies as having a dorsal channel on the fore part o?ili/, (which is indi- 

 stinct in parvula, and rather deep in aurulenta,) and posteriorly hav- 

 ing two longitudinal fovese. 



All the species have a fovea on each side near the lateral margin 

 and at the dilated part of the thorax : these foveae are very large 

 and extend from the margin (where they are broadest) to the dorsal 

 channel, and form a transverse depression in D. pilistriata, castano- 

 ptera, aurulenta, and parvula ; in the remaining species they are con- 

 fined to the margins. In D. pulchella they are very large and rather 

 deep. 



The anterior tibise have generally the external part produced, be- 

 yond the base of the tarsus, into a pointed process : behind this, and 

 still on the external part, there is another pointed, or tooth-like 

 process ; where this obtains I have described the tibiae as bidentate 

 externally. There is also, in some of the species, a tooth-like pro- 

 cess springing, and projecting at right angles, from the apex of the 

 inner part of the tibia ; this last character is peculiar to the males, 

 and is found only in D. Chil^renii, Hopei, affinis, Edwardsii, and 

 splendens*. D. affinis has the outer portion of the anterior tibiae 

 but slightly elongated and the adjoining tooth indistinct, in which 

 respect it differs from those species nearest allied. In D. splendens 

 the two outer processes are closer together than in either D. Chil- 

 drenii, or Edioardsii, and the apical one is recurved. 



In D. splendens and Hopei (and in the females only) there are 

 two short spines on the under part of the basal joint of the tarsus ; 

 a character which separates them from allied species ; the simple an- 

 terior tibia will render it easy to distinguish D. Hopei. 



Species 1. D. sericea. 

 Melolontha sericea. Kirby, in Linn. Trans., vol. xii. p. 463. 



D. viridis, supra sericeo-nitida, pilis sparsis decumbentibus, sub- 

 tus ex pilis albis decumbentibus incana : capite punctulatis- 

 simo : thorace subconico, confluenter punctulatissimo, su- 

 perne subcanaliculato, ad latera subspinoso : scutello acumi- 



* Not having seen a perfect male of D. pulchella, I am not aware whether it pos- 

 sesses this character. D. castanoptera is another species which I must omit to no- 

 tice, not having one by me at present to examine. 



