Food of Insects. 



Insects, like other animals, derive their nourishment from the vege- 

 table and animal kingdoms ; but a glance is sufficient to show, that 

 they possess a much wider field of operations than the others. While 

 the other animals make use for their subsistence of only a small portion 

 of the inexhaustible treasures of the vegetable kingdom, and reject the 

 rest as insipid or noxious, the insects leave perhaps no vegetable pro- 

 duction untouched. From the majestic oak to the invisible fungus, or 

 the insignificant wall-moss, the whole race of plants is a stupendous 

 meal, to which the insects sit down as guests. Even those plants which 

 are highly poisonous and nauseating to other animals are not refused 

 by them. But this is not yet all. The larger plant-consuming animals 

 are usually limited to leaves, seeds, and stalks : not so insects, to the 

 various families of which every part of a plant yields suitable pro- 

 vender. Some which live under the earth attack roots, others choose 

 the stem and branches, a third division lives on the leaves, a fourth 

 prefers the flowers, while a fifth selects the fruit or seed. 



Even here a still further selection takes place. Of those which feed 

 on the roots, stem, and branches, some species only eat the rind, like 

 the bee-hawkmoth (Sphinx apiformis) ; others the inner bark and the 

 alburnum, like the Tortrix Wceberiana, and the injurious bark-beetle ; 

 and a third division penetrates into the heart of the solid wood, like 

 the goat-moth (Cossus ligniperda), and the family of the long-horned 

 beetles (Cerambycidas). 



Of those which prefer foliage, some take nothing but the juice out 

 of the veins (aphides, in all their states) ; others devour only the sub- 

 stance of the leaves, without touching the epidermis (mining caterpillars); 

 others only the upper or under surface of the leaves (many leaf-rollers, 

 Tortrices) ; while a fourth division devours the whole substance of the 

 leaf (the larvae of many Lepidopterous insects). 



Of those which feed on flowers, there are some which eat the petals 

 (the larvaB of Noctua verbasci, the mullein-moth, N. Iinaria3, &c.) ; 

 others choose the farina in a perfect state (bees, the rose-chafer, Ce- 

 tonia, the Lepturidas, &c., &c.) ; and a still greater number the honey 

 from the nectaries (most perfect Lepidopterous insects, wasps, and 

 flies). There are also insects which, not satisfied with any existing 

 part of the plants as such, cause injury to one part or another, by 

 occasioning a peculiar body or excrescence in which their young live, 

 as the various sorts of gall insects and other sorts of flies. But insects 

 are not confined to plants alone in their living and unused state. The 

 death-watch, or ticking-beetle (Anobium), feeds on wood which for 

 years has been used in our dwellings in various articles of furniture 

 and utensils. 



From what has been said it will appear, that a single plant can sup- 

 port a host of various sorts of insects on its different parts ; whence 

 it also appears, that the number of insects greatly exceeds that of 

 plants. 



