Anatomy of Insects. 51 
CHAPTER 1. 
ANATOMY AND PHYSIOLOGY. 
In this chapter I shall give first the general anatomy of 
insects; then the anatomy, and still more wonderful physi- 
ology, of the honey bee. 
ANATOMY OF INSECTS. 
In all insects the body is divided into three well-marked 
portions (Fig. 2.); the head (Figs. 5 and 6), which con- 
tains the mouth organs, the eyes, both the compound and, 
when present, the simple, and the antenne; the thorax, 
which is composed of three rings, and gives support to the 
one or two pairs of wings, when present, and to the three 
pairs of legs; and the abdomen, which is composed of a 
variable number of rings, and gives support to the exter- 
nal sex organs, and when present, to the sting. Within 
the thorax there are little more than muscles, as the con- 
centrated strength of insects, which enables them to fly 
with such rapidity, dwells in this confined space. Within 
the abdomen, on the other hand, are the sex organs, by far 
the greater and more important portions of the alimentary 
canal, and other important organs, 
ORGANS OF THE HEAD, 
Of these the mouth organs (Fig. 8) are most prom- 
inent. These consist of an upper lip—labrum; and under 
lip—labium, and two pairs of jaws which move sidewise; 
the stronger, horny jaws are called mandibles, and the 
more membranous, but usually longer, are named maxille. 
The labrum (Fig. 8, 7) is well described in the name upper 
lip. It is attached, usually, by a movable joint to a simi- 
larly shaped piece above it, called the clypeus (Fig. 8, ¢), 
ard this latter to the broad epicranium (Fig. , 0) which 
contains the antennz, the compound, and, when present, 
the simple eyes (Fig. 5). 
The labium (Fig. 35) is not described by the name 
under lip, as its base forms the floor of the mouth and its 
