COLEOPTERA 



The members of the genus Sttpha are very much flattened (F 

 The prothorax is round in outline, with very thin edges which 

 the wing-covers somewhat. The body is not nearly as stout 

 as that of a burying-beetle, being fitted for creeping under 

 dead animals instead of for performing deeds requiring great 

 strength. Silpha bituberosa, which is known as the spinach 

 carrion-beetle, feeds on spinach, beets, and other plants, in 

 the West. 



In some of the minute members of this family the body 

 is nearly hemispherical. 



143 



ig. 241). 

 overlap 



Fig. 242. 



Family Staphylinid^ 



The Rove-beetles 



The rove-beetles are very common about decaying animal matter, 

 and are often found upon the ground, under stones or other objects. 

 They are mostly very small insects; a few species, however, are of larger 

 size, measuring \ inch or more in length. Their appear- 

 ance is very characteristic, the body being long and slender, 

 and the wing-covers very short (Fig. 242). The wings, 

 however, are fully developed, often exceeding the abdomen 

 in length ; when not in use the wings are folded beneath the 

 short wing-covers. The abdominal segments are freely 

 movable. 



It is interesting to watch one of these insects fold its 

 wings; frequently they find it necessary to make use of the 

 tip of the abdomen or of one of the legs in order to get the 

 wings folded beneath the wing-covers. 



The rove-beetles can run quite swiftly; and they have the curious 

 habit, when disturbed, of raising the tip of the abdomen in a threatening 

 manner, as if they could sting. As some of the larger species resemble 

 wasps somewhat in the form of the body, these threatening motions are 

 often as effective as if the creatures really had a sting. William Becbe 

 states (Atlantic Monthly, October, 1919) that when some rove-beetles 

 were attacked by ants they raised their tails and ejected a drop or two 

 of a repellent fluid which drove the ants away. This observation indi- 

 cates the probable explanation of the actions of these beetles when dis- 

 turbed. 



As these insects feed upon decaying animal and vegetable matter, 

 they should be classed as beneficial. The larvas resemble the adults 

 in the form of the body and are found in similar situations, about decay- 

 ing animal and vegetable matter, beneath bark and in fungi. Some 

 species are guests in the nests of ants, and others in the nests of termites. 

 Nearly three thousand North American species of rove-beetles have 

 been described. The great majority are small and exceedingly difficult to 

 determine. Among the large species that are common are the following. 

 Creophilus maxillosus. — This species varies from \ an inch to nearly 

 an inch in length. It is of a shining black color, spotted with patches of 

 fine gray hairs. There is a conspicuous band of these across the middle 

 of the wing-covers, and another on the second and third abdominal seg- 



