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A cigar box and a bottle with a notched cork may be used for holding specimens. Cigar boxes may be used for holding collections of dried insects. Cork or ribbed packing paper may be fixed in the bottom for supporting the insect pins. Moth balls or tobacco may be placed in each box to keep out the insect pests which infest collections.

It is pleasant and profitable to take to the fields a small book like this one, or even Comstock's "Manual of Insects," or Kellogg's "American Insects," and study the insects and their habits where they are found.

Captured insects which, in either the larval or perfect stage, are injurious to vegetation, should always be killed after studying their actions and external features, even if the internal structure is not to be studied. Beneficial insects, such as ladybugs, ichneumon flies, bees, mantis (devil's horse), dragon flies, etc., should be set free uninjured.

The body of an insect (e.g. a wasp, Fig. 122) is divided by means of two marked narrowings into three parts: the head (K), chest (B), and abdomen (H).

The head is a freely movable capsule bearing four pairs of appendages. Hence it is regarded as having been formed by the union of four rings, since the ancestor of the insects is believed to have consisted of similar rings, each ring bearing a pair of unspecialized legs. The early grub or caterpillar stage of insects is believed to resemble somewhat the ancestral form.

The typical mouth parts of an insect (Fig. 123), named in order from above, are (1) an upper lip (labrum, ol) (2) a