INDIKECT BENEFITS DERIVED FROM INSECTS. 237 



Almost all were massacred in the space of a few days without 

 distinction of age or sex, and devoured by the survivors. He 

 informs us also that they often devour their own offspring as 

 soon as they are born. ' Spiders are equally ferocious in their 

 habits, fighting sanguinary battles, which sometimes end in 

 the death of both combatants ; and the females do not yield 

 to the Mantes in their unnatural cruelty to their mates. Woe 

 be to the male spider that, after an union, does not with all 

 speed make his escape from the fangs of his partner ! Nay, 

 De Geer saw one that, in the midst of his preparatory caresses 

 was seized by the object of his attentions, enveloped by her in 

 a web, and then devoured — a sight which, he observes, filled 

 him with horror and indignation.^ 



Such are the benefits which we derive from the insects that 

 keep each other in check. Here they are the destroyers to 

 which we are chiefly indebted ; but Ave are in another jDoint 

 of view under nearly equal obligations to the destroyed ; for 

 they are insects, either wholly or in part, that form the food 

 of some of our most esteemed fishes, and of birds that are not 

 more valuable to us as articles for the table, than as the 

 songsters that enliven our groves. But before proceeding to 

 the details which this view of the subject involves, I ought 

 not to omit pointing out to you that many quadrupeds, which, 

 though not all of direct utility to us, are doubtless of import- 

 ance in the scale of being, derive a considerable part of their 

 subsistence from insects. 



The harmless hedgehog and the mole, to begin at the lower 

 end of the series, are both said to be insectivorous^^; the latter 

 devouring large quantities of the wire-worms. The greedy 

 swine will root up whole acres in search of the grubs of 

 cock-chafers, of which they are very fond ; and perhaps the 

 good they do is greater than the harm, if their attack be 

 confined to grass that having been undermined by these grubs 

 would soon die : they also dig up the larvae of the destructive 

 Cicada septendecim, called the American locust^, on which, 

 when in their perfect state, the squirrels are said to grow fat.^ 



1 De Geer, vii. 335. 

 4 Bingley, iii. 27. 



2 Ibid. 180. 3 Bingley, ii. 374. 



5 Collinson in Pkilos, Trans. 1763. 



