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Fig. 135.—Honey-bee’s foot in the act of climbing, showing the automatic action of the pulvillus, × 30: A, position of foot in climbing on a slippery surface, or glass; pv, pulvillus; fh, tactile hairs; un, unguis; t, last tarsal joint. B, position of foot in climbing rough surface. C, section of pulvillus just touching flat surface; cr, curved rod. D, the same applied to the surface.—After Cheshire.

Climbing.

The best climbers are obviously those insects which live on trees and bushes, as, for example, longicorn beetles and grasshoppers. These may be accurately called the monkeys of the insect kind, even if their movements take place less gracefully, and indeed rather stiffly and woodenly. We already know what are the proper climbing organs; that is, the sharp easily movable claws on the foot. With the help of these claws certain insects, May-beetles for example, can hang upon one another like a chain; indeed, bees and ants in this manner bind themselves together into living garlands and bridges. There are still added to the chitinous hooks flaps and balls of a sticky nature, by help of which likewise the insects glue themselves together. To facilitate the spanning of still thicker twigs, the climbing foot of insects has a greater movability even than when it only serves as a sole. (Graber.)