274 MOTIONS OF INSECTS. 



weevil (Curculio Nucum, L.)- When placed upon a 

 table, after lying some time, perhaps, bent in a bow, 

 with its head touching its tail, at last it begins to move, 

 which, though in no certain direction, it does with 

 more speed than might be expected. Rosel fancied 

 that this animal had feet furnished with claws ; but in 

 this, as De Geer justly observes, he was altogether 

 mistaken, since it has not the least rudiment of them, 

 its motion being produced solely by the alternate con- 

 traction and extension of the segments of the body, as- 

 sisted, perhaps, by the fleshy prominences of its sides. 

 — T-Other larvae have this annular motion aided by a 

 slimy secretion, which gives them further hold upon 

 the plane on which they are moving, and supplies in 

 some degree the place of legs or claws. That of the 

 weevil of the common figwort {Ciomts Scrophularice, 

 Latr.) is always covered with slime, which enables it, — 

 though it renders its appearance disgusting, — to Malk 

 with steadiness, by the mere lengthening and shortening 

 of its segments, upon the leaves of that plant ^. — Of this 

 kind also are those larva*, mentioned above'', received 

 by De Geer from M. Ziervogel, which, adhering to 

 each other by a slimy secretion, glide along so slowly 

 upon the ground as to be a quarter of an hour in going 

 the breadth of the hand, whence the natives call their 

 bands Gards-drag'^. 



As a further help, others again call in the assistance 

 of their unguiform mandibles. These, which are pe- 

 culiar to grubs with a variable membranaceous head, 

 especially those of the fly tribe (3Iifscidce), when the 

 animal does not use them, are retracted not only within 



2 Dt: Gccr, v. 2ia. " See above, p. 8. " De Geer, vi. 33S. 



