412 MEANS OF DEFENCE OF INSECTS. 



This insect, when alarmed, rolls itself up into a little ball. In this attitude 

 its legs and the underside of the body, which are soft, are entirely covered 

 and defended by the hard crust that forms the upper surface of the animal. 

 These balls are perfectly spherical, black and shining, and belted with 

 narrow white bands, so as to resemble beautiful beads ; and could they be 

 preserved in this form and strung, would make very ornamental necklaces 

 and bracelets. At least so thought Swammerdam's maid, who, finding a 

 number of these insects thus rolled up in her master's garden, mistaking 

 them for beads, employed herself in stringing them on a thread ; when, to 

 her great surprise, the poor animals beginning to move and struggle for 

 their libertv, crying out and running away in the utmost alarm, she threw 

 down her prize. 1 The golden-wasp tribe also (Chrysididts), all of which I 

 suspect to be parasitic insects, roll themselves up, as I have often observed, 

 into a little ball when alarmed, and can thus secure themselves the 

 upper surface of the body being remarkably hard, and impenetrable to 

 their weapons from the stings of those Hymenoptera whose nests they 

 enter with the view of depositing their eggs in their offspring. Latreille 

 noticed this attitude in Parnopes carnea, which, he tells us, Bembex ro- 

 strata pursues, though it attacks no other similar insect, with great fury ; 

 and, seizing it with its feet, attempts to dispatch it with its sting, from 

 which it thus secures itself. 2 M. Lepelletier de Saint-Fargeau, to whom 

 entomology is indebted for so many new facts relative to the manners of 

 hymenopterous insects, has given us a striking account of a contest be* 

 tween the art of one of these parasites (Hedychrum regium) and the 

 courage of one of the mason-bees, in endeavouring to defend its nest from 

 its attack. The mason-bee had partly finished one of her cells, and flown 

 away to collect a store of pollen and honey. During her absence the 

 female parasitic Hedychrum, after having examined this cell by entering it 

 head foremost, came out again, and walking backwards, had begun to 

 introduce the posterior part of her body into it, preparatory to deposit- 

 ing an egg, when the mason-bee arriving laden with her pollen paste threw 

 herself upon her enemy, which, availing herself of the means of defence 

 above adverted to, rolled herself up into a compact ball, with nothing but 

 the wings exposed, and equally invulnerable to the sting or mandibles of 

 her assailant. In one point, however, our little defender of her domicile 

 saw that her insidious foe was accessible ; and, accordingly, with her 

 mandibles cut off her four wings, and let her fall to the ground, and then 

 entering her cell with a sort of inquietude, deposited her store of food, 

 and flew to the fields for a fresh supply ; but scarcely was she gone before 

 the Hedychrum, unrolling herself, and, faithful to her instinct and her object, 

 though deprived of her wings, crept up the wall directly to the cell from 

 whence she had been precipitated, and quietly placed her egg in it against 

 the side below the level of the pollen-paste, so as to prevent the mason-bee 

 from seeing it on her return. 3 



Other insects endeavour to protect themselves from danger by simu- 

 lating death. The common dung-chafer (Geotrupes stercorarius), when 

 touched, or in fear, sets out its legs as stiff as if they were made of iron- 

 wire which is their posture when dead and remaining perfectly 

 motionless, thus deceives the rooks which prey upon them, and, like the 



i Hill's Swamm. i. 174. * Ann. du Mus. 1810, 5. 



* Encycl. Method, x. 8. Lacordaire, Introd. a fEntom. ii. 488. 



