i54 THE STUDY OF INSECTS 



Family Scarab^id^e 

 The Scarabceids or Lamellicorn Beetles 



This very large family is represented in our fauna by nearly one thou- 

 sand species, and includes beetles that exhibit a wide range of variation 

 in size, form, and habits. They are mostly short, stout-bodied beetles, 

 of which the well-known June-bugs or May-beetles represent the most 

 familiar type. The most useful character for distinguishing these insects 

 is the lamellate form of the club of the antennae, the segments constitut- 

 ing it being greatly flattened, and capable of being brought close to- 

 gether. It is this character that suggests the name lamellicorn beetles. 



According to their habits, the members of this family can be sep- 

 arated into two well-marked groups — the scavengers and the leaf- 

 chafers. 



THE LAMELLICORN SCAVENGERS 



The lamellicorn scavengers in both the larval and adult states feed 

 upon decaying vegetable matter. Nearly all the species live in dung, 

 chiefly that of horses and cows; but a few species feed upon fungi. The 

 following are the more common representatives of this division. 



The tumble-bugs. — These are the most familiar of all dung-beetles, 

 for their peculiar habits have attracted much attention from the earliest 

 times. They are of rounded form, and the wing-covers are shortened so 

 as to expose the tip of the abdomen. They are generally black, but 

 some are colored with rich metallic hues. They vary greatly in size. 



The name tumble-bug refers to the habit which many species exhibit 

 of forming round balls of dung, which they roll long distances and then 

 bury. They often work in pairs and it was formerly believed that such a 

 pair was a male and a female working together to make provision for 

 their progeny; but Fabre found by dissecting the beetles that the two 

 members of a pair often proved to belong to the same sex; and concluded 

 that the eager fellow- worker, under the deceitful pretense of lending a 

 helping hand, nurses the scheme of purloining the ball at the first oppor- 

 tunity. 



According to the observations of Fabre, the balls made early in the 

 year are devoured by the beetles, which bury themselves with them and 

 feed upon them. Later, other balls are made and buried, upon each of 

 which an egg is laid. The larva hatching from this egg feeds upon the 

 ball of dung, and when full-grown transforms within the cavity in which 

 the ball was placed. 



This strange habit of rolling these balls has occasioned much specula- 

 tion as to its object, and has been the source of many superstitions, 

 especially in ancient times. The only reasonable theory that we have 

 met is that, as many predacious insects frequent the masses of dung from 

 which the balls are obtained, in order to prey upon the larvae which live 

 there, the more intelligent tumble-bugs remove the food for their larva? 

 to a safe distance. 



The most noted member of this group of genera is the sacred beetle 

 of the Egyptians, Ateuchus sdcer. This insect was held in high veneration 

 by this ancient people. It was placed by them in the tombs with their 



