CHAPTER II. 
INSECTS AND THEIR NEAR RELATIVES. 
Branch ARTHROPODA (Ar-throp'o-da). 
The Arthropods ( Ar'thro-pods ). 
If an insect, a spider, a scorpion, a centipede, or a lobster 
be examined, the body will bo found to be composed of a 
series of more or less similar rings or seg¬ 
ments joined together; and some of these 
segments will be found to bear jointed 
legs (Fig. i). All the animals possessing 
these characteristics are classed together 
as the Branch Arthropoda. 
A similar segmented form of the body 
is found among worms; but these are dis¬ 
tinguished from the Arthropods by the 
absence of legs. It should be remembered 
that many animals commonly called worms, 
as the tomato-worm, apple-worm, etc., ar& 
not true worms, but are the larvae of in¬ 
sects (Fig. 2). The angle-w'orm is the 
most familiar example of a true worm. 
The Branch Arthropoda is the largest 
of the branches of the Animal Kingdom, 
including many more knov-n species than ail the other 
branches taken together. Our common representatives are 
distributed among four classes: these are the Crustacea, 
the Arachnida, the Myriapoda, and the Hexapoda. The 
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