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clothed with scales, which act asa protection to the proboscis. In the flea the 
middle lancet seems to represent the upper lip. 
In bees the lower lip and maxille form together a sucking apparatus, but. 
they are also provided with well developed upper jaws or mandibles. 
In the front part of the face of an insect are two appendages, which vary 
very much in form, in the different sub-orders and genera, and even in the sexes- 
of one species ; they are called antenne. What the exact functions are of these 
important organs, is not known, but it is probable they have more uses than 
one. Experiments have been made with moths in which it was observed that if 
the antennz were removed the insect seemed unable to direct its flight. It is 
probable too that the olfactory nerve is situated in the antennez. The different 
forms which the antennze take have been made use of by entomologists in 
classifying insects. 
The next division of the body of an insect is the thorax. This is the solid 
portion which bears the organs of locomotion, and comprises the three segments. 
which follow the head. The first one is called the pro-thorax and bears the first 
pair of legs, the next or middle segment is called the meso-thorax and supports: 
the second pair of legs and the anterior pair of wings, the third segment is called 
the meta-thorax, and to it are attached the third pair of legs and the hind wings.. 
The wings aie objects of great beauty and strength, aud consist, asa rule, of a 
double membranous plate, traversed more or less, by bony veins. 
The last division of an insect’s body is the abdomen, which consists of a series 
of segments attached by membranes. Each of these segments is formed of two 
’ arcs or semi-segments, one above and the other below. Theabdomen is the seat of 
the organs of reproduction andalimentation. The senses of insects are dependent 
upon the nervous systen, which consists of a series of nervous masses or ganglia, 
joined together by two nervous threads, the whole constituting a nervous chain, 
from which nerves ramify to the different organs, enduing them with the various 
senses they possess ; from the first ganglion the nerves of the eyes and antenne 
are fed, and from the second themouth. Hearing and smell are certainly possessed 
by insects ; but their appropriate organs are not ascertained. They also possess 
taste, sight, and touch, the latter being seated probably in the antenne, the palpi 
and in the tarsi of the feet. 
The circulatory system is well represented in insects. The blood is generally 
colorless, but occasionally of a greenish or reddish hue. The heart, which com-, 
prises a series of large reservoirs in the form of a long tube plainly discernible 
through the transparent skins of caterpillars, lies above the alimentary canal on 
the upper surface of the body. 
Insects do not breathe, like large animals, through their mouths ; but by 
means of breathing-holes in their sides, which connect with two great air canals. 
