FLOWERS AND INSECTS. The dependenee of insect life on that of plants is illustrated by the fact that in Germany between 500 and OM species of insects obtain their livelihood by feeding upon the oak, while in the United States nearly the same number of species have already been found to prey on the native oaks. The elm, wil lows, and pines also afford food and shelter to hundreds of species, the insect pests of the apple and other fruit trees also amounting to many hundred species each. Some insects bore in the roots: multitudes of borers penetrate into the trunk, branches, and twigs, as well as hark: while still greater of caterpillars feed upon the leaves The result of the life within the tree—in the \%00,1 or bath, or in veining the leaves—is very marked, a, the borers are pro foundly modified in latil1n-• Nlany borers, ill V1111,11111'llee Of their pet illiar mode of life, have long, often ilattenctl, bodies, are eyeless, and h:n'c lost their linnhs, in part, or wholly, through disuse, NI hy ohich they oat their way through the wood. are enlarged ;Intl other wise adapted for their ligelivorous haleits. 'I he
manifold adaptations of the la rua. of beetles, as seen in thousand. of species, admirable examples, in the opiniem of Lanuarekians, of the effects upon a plastic organism of strains, stresses, and of use and disuse, in the produet ion of the form of the body. It may said in gen eral that as .1011 more or less tree like in habit. however low or primitive in char appeared I such a- tree-like. chile and allied flowerless forms of the Devonian and (*a rhoniferons periods . a uetc world hitherto unoccupied was opened up to insect. life, of which the insects speedily took advantage.
The earliest insects, as eockroaches. locusts, and the feel on dead leaves or herbaceous plants ; others were to it. a lid carnivorous.
But as soon as plants became tree like and grew in vast forests. new habitats were opened up, of which the insect• immediately took advantage It will thus be seen that the intimate relation be tweet] plants and insects most have taken place very early in geological history.