INSTINCT OF INSECTS. 541 



seams of its coat ; and as the little miner is not embarrassed with the 

 removal of the excavated materials, which it swallows as it proceeds, a 

 cavity sufficiently large is but the work of a few hours. It then lines it 

 with silk, at the same time pushing it into a more cylindrical shape ; and 

 lastly, cutting it off at the two ends and inner side, it sews up the latter 

 with such nicety that the suture is scarcely discoverable ; and is now pro- 

 vided with a case or coat exactly fitting its body, open at the two ends, 

 by one of which it feeds, and by the other discharges its excrement, having 

 on one side a nicely joined seam, and the other that which is commonly 

 applied to its back composed of the natural marginal junction of the 

 membranes of the leaf. 



Such are the ordinary operations of this insect, which when it is 

 considered that the case is rather fusiform than cylindrical ; that the end 

 through which it eats is circular, and the .other curiously three-cornered 

 like a cocked hat ; and that consequently its cloth requires to be very 

 irregularly and artfully cut to be accommodated to such a figure, it must 

 be admitted, are the result of an instinct of no very simple kind. Compli- 

 cated, however, as these manoeuvres seem, our ingenious workman is not 

 confined to them. By way of putting its resources to the test, Reaumur 

 cut off the serrated edge from the nearly finished coat of one of them, and 

 exposed the little occupant to the day. He expected that it would have 

 quitted its mutilated garment and commenced another ; and so it certainly 

 would, had it been guided by an invariable instinct. But he calculated 

 erroneously. Like one of its brother tailors of the biped race, it knew 

 how, " to cut its coat according to its cloth," and immediately setting 

 about repairing the injury sewed up the rent. Nor was this all. The 

 scissors having cut off one of the projections intended to enter into the 

 construction of the triangular end of its case, it entirely changed the 

 original plan, and made that end the head which had been first designed 

 for the tail. 



On another occasion Reaumur observed one of these larvae to cut out 

 its coat from the very centre of a leaf, where it is obvious a series of ope- 

 rations wholly different must be adopted, the two membranes composing 

 it necessarily requiring to be cut and sewed on two sides instead of on one 

 only. But what was most striking in this new procedure was the altera- 

 tion which the caterpillar made in the period of sewing up its garment. 

 When these larvae cut out their case from the edge of a leaf, they seem 

 aware that if they were to detach it entirely from the inner side before the 

 process of sewing, lining, &c., is completed, having no support on the 

 exterior edge, it would be liable to. fall down ; at the same time they 

 could not sew together the membranes composing it at the inner side, 

 without cutting them in part from the leaf. While, therefore, they divide 

 the major part of their inner side from the leaf, they artfully leave them 

 attached to it by one of the large nerves at each end ; and these supports 

 they do not cut asunder until the intermediate space has been sewed up, 

 and they are ready to step, with their house on their back, upon the terra 

 firwa of the disk of the leaf. In this instance, therefore, the larvae do not 

 wholly separate their case from the leaf, until it is sewed. But when the 

 same larvae cut out their materials from the middle of the leaf, where, 

 though completely cut round, they are retained in their situation secure 

 fronTall danger of falling by the serratures of the incisions made by the 

 jaws of the larvae, these little tailors vary their mode, and entirely detach 



