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Episternum. — The pleural sclerites are distinct ; the epis- 

 ternum is large, angularly concave, and does not reach the 

 coxa. It bears near its cephalic margin two, transversal, 

 raised lines or carinae, one of which is a continuation of the 

 collar-making carina of the sternum. Like the sternum, the 

 cephalic margin of the episternum fits into the prothorax. 

 The lateral margin is angularly inflexed along its entire 

 length, as is the case with all the pleural sclerites. The 

 narrow, inflexed portion is covered when the wing-covers are 

 closed by the inflexed, lateral margin of the wing-covers. 



Epimeron. — The epimeron, lying along the caudal margin 

 of the episternum, is a narrow, transversal sclerite. Its mesal 

 extremity does not reach the coxal cavity, but lies contigu- 

 ous to the lateral margin of the metasternum. 



Paraptera or Elytra. — The paraptera are remarkably de- 

 veloped into strongly chitinized, wing-like structures, called 

 the elytra or wing-covers. When the beetle is at rest, the 

 elytra fit closely over the dorsal aspect of the meso- and meta- 

 thorax and abdomen, protecting the abdomen and wings, 

 which (when present, as in most beetles) 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 present a series of sub-parallel, longitudi- 

 nal, impressed lines, and the lateral margins, termed epipleurce, 

 are inflexed over the dorso-lateral margins of the body. 

 This inflexed condition of the margins does not extend quite 

 to the tips of the elytra, but disappears at a point where the 

 margin appears to be interrupted. On the inner surface of 

 each elytron near the lateral margin there is a distinct longi- 

 tudinal fold or plica. The fore or mesothoracic wings are 

 wanting or are rudimentary in beetles, although the elytra 



