COLEOPTERA. 
559 
III. The Earth-boring Dung-beetles .—These beetles are 
of a rounded convex form (Fig. 676). They differ from all 
other dung-beetles in having the antennae 
eleven-jointed, and in the labrum and man¬ 
dibles being visible from above. This is a 
small group, less than twenty North American 
species having been described. The popular 
name is derived from that of the typical genus, Fig. 676. 
Geotrupes (Ge-o-tru'pes), which signifies earth-boring. Those 
species the habits of which are known live in excrement. 
The females bore holes into the earth either beneath the 
dung or near it; into these holes they convey a quantity of 
the dung: this is to serve as food for the larvae, an egg be¬ 
ing laid in each hole. This is an approach to the peculiar 
habits of the tumble-bugs. 
IV. The Skin-beetles .—The members of this group are 
oblong, convex species, in which the surface of the body 
and wing-covers is usually very rough, and covered with a 
crust of dirt, which is removed with great dif¬ 
ficulty. They are small or of medium size; 
our most common species measure from one 
third to one half inch in length. The abdomen is 
Fig.677. covered by the elytra; the feet are hardly fitted 
for digging, but the femora of the front legs are greatly di¬ 
lated. Our species all belong to the genus Trox (Fig. 677). 
They feed upon dried, decomposing animal matter; many 
species are found about the refuse of tanneries, and upon 
the hoofs and hair of decaying animals. 
THE LAMELLICORN LEAF-CHAFERS. 
The leaf-chafers are herbivorous insects which in the 
adult state usually feed upon the leaves of trees, but many 
of the species devour the pollen and petals of flowers. In 
the larval state some of these insects are found in rotten 
wood ; others live in the ground, where they feed upon 
the roots of grass and other plants. These larvae are thick, 
