2972 THE JOINTED ANIMALS 



are in advance of all other groups. In brightness of color, beauty of pattern, 

 and gracefulness of form some of the species can hardly be equalled even by the most 

 gorgeous birds, while in mechanical perfection of structure, as testified by activity 

 and strength, others of the group are unsurpassed in the animal kingdom. It has 

 been stated that if a man could leap in proportion to his stature as far as a flea can 

 hop, he could clear at a bound a wall over one hundred feet high, and if he could 

 sing as loudly as the cicada, his voice could be heard for a distance of many miles. 

 Indeed, even in matters about which a man is wont to especially pride himself, such 

 as those touching social organization, he might with advantage go to the ant 

 to learn wisdom, since many of the problems of modern civilization, involved in the 

 questions concerned in the regulation of increase of population, the proper division 

 of labor, and the support of useless individuals, have been satisfactorily solved by 

 many of the species of insects that live habitually in communities. 



Speaking in a general way, insects may be said to be terrestrial animals, since 

 all the species are fitted more or less completely for atmospheric respiration and for 

 progression on the land; many of them in addition are furnished with wings, which 

 propel them through the air with amazing velocity. In many of the orders, how- 

 ever, as, for instance, in the beetles and bugs, there are species that have adopted 

 an aquatic mode of life and spend their days in fresh-water ponds and streams in 

 various quarters of the globe. Others again, like some of the gnats and dragon 

 flies, live in fresh water during the larval stages of their existence, but quit it on 

 attaining maturity. Insects, too, are sometimes found on the coast beneath stones 

 and seaweed at low water, but there is only one species of insect that can strictly be 

 called marine; this is a bug {Halobates} sometimes met with in numbers on the 

 surface of the ocean thousands of miles from land. 



The phenomena known as mimicry and protective resemblance are 

 strikingly exemplified in insect life. The term mimicry is usually 

 applied to cases where a species, otherwise unprotected, lives unmolested owing to 

 its resemblance to another which is gifted with defensive weapons in the form of 

 poison glands, or with a nauseating flavor that renders it distasteful. Such species 

 as these are usually rendered conspicuous by contrasting patches of bright color. 

 It is noticeable, for instance, that the patterns of bees and wasps are strikingly 

 diversified, in order that the insects may be readily recognized and not slain by 

 mistake for other species. Bees and wasps, then, being species that enjoy 

 immunity from attack, are often imitated or mimicked by perfectly harmless flies 

 and moths, and some beetles and animals allied to crickets similarly mimic ants. 

 But the phenomenon of protective resemblance or the mimicry of inanimate 

 objects by which a species is rendered practically invisible amongst its surround- 

 ings on account of its resemblance to a leaf, stone, twig, or bird-dropping, is of far 

 commoner occurrence. On the accompanying plate a few instances of this kind 

 of adaptation to surroundings are portrayed. Figs. 12, 13, and 18 are the larvae 

 or caterpillars of different species of L,epidoptera, the first two in color and shape 

 simulating branches, and the last a snail shell; Figs, i, 2, 9, and 14 are leaf-like 

 pupae or chrysalids of other kinds of L,epidoptera; while Figs. 3, 5, 7, n, 15, 23, 

 and 24 are the adult stages of members of the same order under different disguises. 



