PARASITES ON PERFECT INSECTS. 37 



exercised either on living subjects, affording at once a cover 

 for their eggs and nourishment for their young, or else upon 

 those stranger nests wherein is to be found both shelter and a 

 store of living prey suitable for the same purposes. The suf- 

 ferers in these cases are still also immature, being still either 

 in the first or second stage of existence. 



But there are certain other insect parasites (chiefly wingless, 

 and of the order Aptera) which are parasitic entirely for them- 

 selves, perfect insects which infest others, perfect also. Of 

 such are the Acari, or mites, with which all, who have ever 

 noticed the commonest of black beetles, must have sometimes 

 seen them covered, as well as their pretty cousins the gold 

 green chafers of the rose. The humble bee is another not un- 

 frequent sufferer from somewhat similar infestation, which is 

 said, moreover, to rob, occasionally, the merry grasshopper of 

 his juices, if not of his enjoyment. These, however, with 

 other parasitic tormentors whose visitations extend to bird, 

 and beast, and man, may be looked on more properly as a 

 part of the vermin crew, not now the subject of our notice. 



Enough, too, of insect preying upon insect. But before we 

 have done with parasites altogether, we must say a concluding 

 word or two of insects as now and then preyed upon by 

 plants. We are told by physiological botanists, that plants 

 with few and small leaves depend chiefly for their food upon 

 the soil ; those with many and large ones, more upon the at- 

 mosphere ; and in the Chinese air-plant we have the phenome- 



