THE BEETLE AND ITS ALLIES 



47 



Another family of aquatic beetles includes Hydrophilus l 

 and its allies, which are less strictly carnivorous than the 

 last two families. Their antennae are 

 short and club-shaped, and their bodies 

 are plumper than that of Dytiscus, which 

 is of about the same size and lives in 

 similar places. 



The next family includes certain 

 short-winged beetles (Staphylinidte 2 ), 

 so called because the elytra cover only 

 a small part of the abdomen (Fig. 44). 

 These beetles (" rove -beetles") are usu- 

 ally black and of small size. They 

 are very common under decaying or- 

 ganic matter, stones, and other objects 

 lying on the ground. They run swiftly. Some species 

 mimic ants and wasps. Not only do they resemble these 



FIG. 44. A 

 gus, a staphylinid. 

 From Packard. 



FIG. 45. A staphylinid elevating the abdomen. Photo, by W. H. C. P. 



Hymenoptera in the general form of the body, but also in 

 the movements of the tip of the abdomen, which, when the 



1 i>5ajp, water ; 0/Xos, loving. 



2 (rTa^i/AZVos, from crra^iyXiy, a cluster, is Aristotle's name for a certain 

 insect. 



