NO. 13 



STAPH YLINIDAE BLACKWELDER 



65 



cylindrical as in Aleochara (fig. 19 A) and Hahrocerus (fig. 19 E). 

 The middle segment may be greatly expanded as in Stenus (fig. 19 C) 

 or very short as in Trigonurus (fig. 19 H). The terminal segment is 

 generally small and narrow as in Stenus (fig. 19 C), Hypocyptus (fig. 

 19 F), and Paederus (fig. 19 I), but is greatly expanded in Oxyporus 

 (fig. 19 D) into a very large, compressed, obconical body. 



n the labial palpi. 



A, Aleochara lata Grav. B, Liparoccphahis brevipennis Makl. C, Stenus 

 sculptilis Csy. D, Oxyporus lateralis Grav. E, Habrocerus schzvarsi Horn. F, 

 Hypocyptus longicornis (Payk.). G, Pinophilus parvipcnnis Csy. H, Trigo- 

 nurus crotchi Lee. I, Paederus laetus Er. J, Osorius mundus Shp. 



A four-segmented labial palpus was found only in Aleochara (fig. 

 19 A). The palpi of other Aleocharinae are said to be similar. 



THE THORAX 



A great deal of variation is exhibited in the shape of the pronotum 

 (figs. 20, 21). It is hard to classify the types, as nearly all gradations 

 are to be found and nearly every genus or even species is somewhat 

 different from its near, as well as from its more distant, relatives. 

 Figures 20 and 21 show some of the forms that occur. Almost anv 



