longer and cleaner lateral grooves; glossier surface; often some- 

 what smaller size; obsolescence of posteromedian and paramedian 

 grooves in the caudal field of dense punctations; and narrowed 

 posterior margin. Field collected specimens of these two spe- 

 cies that might be confused have not been observed during the 

 present study; Feldman-Muhsam (1954), however, states that 

 laboratory- bred series might be confused. 



Females are easily recognized if only by the genital apron, 

 the character of which is accentuated rather than decreased by 

 enormous engorgement. The apron is a transversely elongate oval 

 of somewhat variable shape; in profile it is surmounted anterior- 

 ly by a naiTow, bulging lip; centrally it is deeply depressed 

 (or concave); posteriorly it is bounded by a more or less dis- 

 tinct lip that never protrudes as much as the anterior lip. 

 Feldman-Muhsam^s (1954.) figure 2F of this apron is a surprising- 

 ly imsatisfactory representation of its actual appearance and 

 supports the assumption that this species did not prosper during 

 the laboratory study devoted to it. 



The scutum of practically every field collected female is 

 blackish and with few punctations among which a few fine ones 

 may be scattered. The scutum of a few specimens bears larger, 

 superficial punctations scattered about its surface; that of 

 greatly engorged specimens, as usual in this genus, is rugose. 

 In the few specimens with a more punctate scuttmi, the genital 

 apron is nevertheless highly distinctive and the glossy scutal 

 appearance Is retGiined. 



Note that no known characters distinguish the females of 

 H. truncatum from those of the less common and more restricted 

 ^. albiparmatum . 



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