556 
THE STUDY OF INSECTS . 
The Horned Passalus, Passalus cornutus (Pas'sa-lus cor- 
nu'tus), differs greatly in appearance from our other stag- 
beetles (Fig. 674). It is a large shining, black beetle, with 
a short horn, bent forwards, on the top of the head. This 
beetle and its larva are found in decaying wood. The larva 
is remarkable for possessing only four well-developed legs. 
Family SCARAB^EID^E (Scar-a-bae'i-dae). 
The Scarabezids (Sea r-a-bee'ids) or the Lamellicorn (.La-metli - 
corn) Beetles . 
This is a very large family, including beetles that repre¬ 
sent 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 constituting it being greatly flattened, and 
capable of being brought close together. It is this character 
that suggests the name lamellicorn beetles. 
According to their habits, the members of this family can 
be separated 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 animal and vegetable matter. 
Nearly all the species live in the dung of animals, chiefly that 
of horses and cows. But the members of one genus, Trox, 
feed upon decaying animal matter, and a few species feed 
upon fungi. The following are the most common represen¬ 
tatives of this division : 
I. The Tumble-bugs .—These are the most familiar of all 
dung-beetles, for their peculiar habits have attracted much at¬ 
tention from the earliest times. They are of rounded form, 
and the wing-covers are shortened so as to expose the tip 
