i 4 2 THE STUDY OF INSECTS 



most common species is Hydrophilus obtusdtus; this measures about f of 

 an inch in length. 



Some of the smaller species of this family are not aquatic, but live 

 in moist earth and in the dung of cattle, where, it is said, they feed on 

 dipterous larvae. 



Family Silphid^e 



The Carrion-beetles 



The carrion-beetles are mostly of medium or large size, many species 

 attaining the length of if inches while the smaller species of the more 

 typical genera are nearly \ inch in length; some members of the fam- 

 ily, however, are minute. The segments near the tip of the antennae 

 are usually enlarged so as to form a compact club, which is neither comb- 

 like nor composed of thin movable plates; sometimes the antennas are 

 nearly filiform. 



These insects usually feed upon decaying animal matter; some, how- 

 ever, feed upon fungi; some on vegetables; and a few species have been 

 known to be predacious when pressed by hunger, destroying living snails 

 and insects, even members of their own species; while a few occur only 

 in the nests of ants. 



It is easy to obtain specimens of these insects by placing pieces of 

 meat or small dead animals in the fields and examining them daily. 

 There are several other families of beetles the members of which can be 

 attracted in this way. 



The larvae also live upon decaying flesh and 

 are found in the same situations as the adults. 



We have in this country more than one hundred 

 species of this family. Our larger and more famil- 

 iar species represent two genera, Necrophorus and 

 SUpha. 



The burying-beetles, Necrophorus. — To this 

 genus belong the larger members of the family. 

 The body is very stout, almost cylindrical (Fig. 

 240). Our common species have a reddish spot on 

 each end of each wing-cover; these spots are often 

 so large that they appear as two transverse bands. 

 In some species the prothorax and the head are 

 FlG - 2 4°- also marked with red. 



These insects are called burying-beetles because they bury carrion. 

 When a pair of these beetles discover a dead bird, mouse, or other small 

 animal, they dig beneath it. removing the earth so as to allow the carrion 

 to settle into the ground. This they will continue until the object is 

 below the surface of the ground. Then they cover it with earth, and 

 finally the female digs down to it and lays her eggs upon it. The larvae 

 that hatch from these eggs feed upon the food thus provided for them. 

 There are many accounts of exhibitions of remarkable strength and sa- 

 gacity by burying-beetles. A pair of these insects have been known to 

 roll a large dead rat several feet in order to get it upon a suitable spot 

 for burying. 



