72 



Make a drawing of the ventral aspect of the entire thorax, 

 including the legs of the left side. 



APPENDAGES OF THE THORAX. 



The hind wings are wanting in this beetle. This is ex- 

 ceptional, however, among beetles, the hind wings, mem- 

 branous and with a few strong veins, being usually well- 

 developed, and differing from the wings of most insects in 

 being folded transversely as well as longitudinally when the 

 insect is at rest. 



The fore-wings are very strongly chitinized and thick- 

 ened, and are called elytra or wing-covers. When the beetle 

 is at rest the elytra fit closely over the dorsal aspect of the 

 meso- and metathorax and abdomen, protecting the abdo- 

 men and hind wings, which (when present, as in most bee- 

 tles) lie folded over the metathorax and abdomen and 

 beneath the wing-covers. The elytra are articulated with 

 the body so as to be freely movable, being outspread when 

 the beetle is in flight. The basal or articulating parts of 

 the elytra lie just ventro-laterad of the lateral margins of 

 the scutellum. The expanded flap or wing-like parts pre- 

 sent a series of sub-parallel, longitudinal, impressed lines, 

 and the lateral margins, termed epipleurcz, are inflexed over 

 the dorso-latera] margins of the body. This inflexed con- 

 dition of the margins does not extend quite to the tips of 

 the elytra, but disappears at a point where the margin ap- 

 pears to be interrupted. On the inner surface of each ely- 

 tron near the lateral margin there is a distinct longitudinal 

 fold or plica, 



PARTS OF THE ABDOMEN. 



The abdomen is composed of a number of very much 

 flattened segments ; and its dorsal surface or tergum is com- 

 pletely covered by the elytra when they are closed. On the 



