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Fig. 139.—May Fly. What order (see table)?

Fig. 140.—Silver Scale. (Order?)

Exercise in the Use of the Table or Key.—Write the name of the order after each of the following names of insects:—

Wasp (Fig. 122)
Weevil (Fig. 163)
Squash bug (Fig. 184)
Ant lion (Fig. 170)
Dragon fly (Fig. 177)
Ichneumon fly (Fig. 159)
House fly (Fig. 172)
Flea (Fig. 173)
Silver scale or earwig (Fig. 140)
Codling moth (Fig. 141)
Botfly (Fig. 138)

Moths and Butterflies.—Order ——? Why —— (p. 82)?

The presence of scales on the wings is a never-failing test of a moth or butterfly. The wings do not fold at all. They are so large and the legs so weak and delicate that the butterfly keeps its balance with difficulty when walking.

The maxillæ are developed to form the long sucking proboscis. How do they fit together to form a tube? (See Fig. 147.) The proboscis varies from a fraction of an inch in the "miller" to five inches in some tropical moths, which use it to extract nectar from long tubular flowers. When not in use, it is held coiled like a watch spring under the head (Fig. 148). The upper lip (labrum), under lip (labium), and lip fingers (labial palpi) are very small, and the mandibles small or wanting (Fig. 146).

The metamorphosis is complete, the contrast between the caterpillar or larva of the moth and butterfly and the adult form being very great. The caterpillar has the three pairs of jointed legs typical of insects; these are