CHAP. II FOOD OF INSECTS 35 



with its stems and foliage, down to the tiny fungus 

 scarcely visible to the naked eye, perhaps not a single 

 plant exists which does not furnish forth delicious 

 eating to some one of the vast tribes of insects. How 

 different it is with the more imposing beings ! To 

 them a considerable amount of vegetation is abso- 

 lutely poisonous the acrid euphorbias, the henbane, 

 hemlock, and deadly nightshade, and a still greater 

 proportion, if it is not actually injurious, is so dis- 

 tasteful as to be seldom or never utilised. The 

 common nettle is by no means highly esteemed 

 by ourselves or by the higher animals in general, 

 yet it is all-important to insects, since it sustains 

 the life, so at least it has been computed, of no 

 fewer than thirty distinct species ; and the cabbage, 

 while it is serviceable enough in its way to man, is of 

 inestimable value to insects, which to the number of 

 two hundred kinds feed upon its substance, or upon 

 insect vegetarians that indulge in this diet. 



The larger herbivorous animals have to remain con- 

 tent with certain parts of plants. They can subsist 

 upon the leaves, the seeds, the fruits, occasionally on 

 the tender stems and roots ; the flowers are attacked 

 rarely, the woody trunks of trees never; but to insects 

 no portion could be named that ever comes amiss. 

 Not that insects are indiscriminate feeders, generally 

 speaking ; far from it. Many are restricted to one 

 particular sort of plant, and having fed for a time on 

 it, will die rather than partake of change, and their 

 size is such that they can select a special portion with 

 the utmost nicety. Among those that appreciate the 

 roots and stems, some confine themselves solely to the 



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