160 INDIRECT BENEFITS DERIVED FROM INSECTS. 



until one only survived l ; and De Geer relates several similar instances.' 

 The younger larvae of Calosoma Sycophanta often take advantage of the 

 helpless inactivity into which the gluttony of their maturer comrades has 

 thrown them, and from mere wantonness, it should seem, when in no need 

 of other food, pierce and devour them. A ferocity not less savage exists 

 amongst the Mantes. These insects have their fore-legs of a construction 

 not unlike that of a sabre ; and they can as dexterously cleave their anta- 

 gonist in two, or cut off his head at a stroke, as the most expert hussar. 

 In this way they often treat each other, even the sexes fighting with the 

 most savage animosity. Rosel endeavoured to rear several specimens of 

 M. religiosa, but always failed, the stronger constantly devouring the 

 weaker. 3 This ferocious propensity the Chinese children have, according 

 to Mr. Barrow, employed as a source of barbarous amusement, selling to . 

 their comrades bamboo cages containing each a Mantis, which are put 

 together to fight. You will think it singular that both in Europe and 

 Africa these cruel insects have obtained a character for gentleness of dis- 

 position, and even sanctity. This has arisen from the upright or sitting 

 position, with the fore-legs bent, assumed in watching for their prey, 

 which the vulgar have supposed to be a praying posture, and hence adopted 

 the belief that a child or traveller that had lost his road would be guided 

 by taking one of these pious insects in his hand, and observing what way 

 it pointed. Mantis fausta, though not as sosne suppose worshipped by 

 the Hottentots, is yet greatly esteemed by 'them, and they regard the 

 person upon whom it alights as highly fortunate. 4 A similar unnatural 

 ferocity is exhibited by Gryllus campestris, of which, having put the sexes 

 into a box, I found on examining them that the female had begun to make 

 her meal off her companion. The malign aspect of the scorpion leads us 

 to expect from it unnatural cruelty, and its manners fulfil this expectation. 

 Maupertuis put a hundred scorpions together, and a general and murderous 

 battle immediately began. 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. 5 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. 6 



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 we are in another point of view under nearly equal obliga- 

 tions to the destroyed; for they are insects, either wholly or in part, that 



1 Reaumur, ii. 413. This habit is well known to our practical Lepidopterists, who 

 have given the name of the Monster Caterpillar to one of these cannibal species ; a 

 memoir upon which by Mr. Thrupp was lately read before the Entomological Society. 



2 De Geer, i. 533. iii. 361. v. 400. vi. 91. * Rosel, iv. 96. 

 * Thunberg's Travels, ii. 66. 



5 De Geer, vii. 335. 6 ibid. 180. 



