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cephalic halves of the metacoxse. The "saddle-flaps," or 

 lateral lobes of the metasternum expand laterad, and their 

 cephalic margins, concavely rounded, form the caudal bound- 

 aries of the mesocoxal cavities. There is a line or suture 

 running transversely across the metasternum near the caudal 

 margin which does not reach the lateral margins. That 

 portion of the metasternum caudad of this suture is called 

 the antecoxal piece of the metasternum. 



Epistermwi. — The rhomboidal epislernum is the largest 

 of the pleural sclerites. 



Epimeron. — The trapezoidal epimeron, though smaller 

 than the episternum, is broader, and more conspicuous than 

 that of either of the other thoracic segments. 



Paraptera. — The paraptera, lying on the dorsal aspect of 

 the body beneath the elytra, are small and weakly chitinized, 

 and may not be determined satisfactorily by the student. 



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



APPENDAGES OF THE THORAX. 



Both fore and hind wings are wanting in this beetle. This 

 is exceptional, however, among beetles, the hind wings, 

 membraneous 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 legs are adapted for running, being long and slender. 

 The pro- and mesocoxse are globular, and the trochanters 

 distinct, but small. In the hind legs the coxse are large and 

 greatly expanded transversely, extending laterad as far as 

 the lateral margins of the metasternum. The coxee become 

 narrower laterad, tapering to an acute point. The trochant- 

 ers of the hind legs are very large and lobe-like. They pro- 

 ject along the basal half of the femur. The tarsi of all the 

 legs are distinctly 5 -segmented. 



