124 



INSECT TRANSFORMATIONS. 



great deal of trouble, by alternately stretching out and 

 contracting them, that it succeeds in rending this, and 

 sets itself at liberty,* Even then the young spider can 

 neither spin a web nor catch prey; for it is still en- 

 veloped in an extremely delicate membrane, which it 

 does not moult unless the weather is favourable and 

 fine.t 



Hatcliing of the epg of the garden spider ('Spr/rrt dutdemu). a, natural 

 size, h^vgg magnified, tht^ cii atriciila (a vvliite spot) in the front, t,', the 

 germ enlarged; «, the head, and k, the body of tlie embryo. </, the em- 

 bryo spider ready to cast off its first skin. 



The latter circumstance will enable us to explain 

 some experiments made by Redi, who kept spiders 

 newly hatched for many months without Ibod.j In 

 the experiments made by us upon the eggs of the wolf 

 spider [Lycosa saccata), we more than once kept the 

 young in boxes, where they were forgotten and without 

 food; and we uniformly found that they remained lively 

 and well so long as they did not cast their embryo 

 skin; but when they did moult, they could not long 

 survive the want of sustenance. § 



In the eggs of moths, the embryo, previous to ex- 

 clusion, may be seen through the shelly snugly coiled 



* De Geer, Mem. vii, p. 196. 



t Diet. Classique d'Hist. Nat. xii, 141. . 



t Redi, Esperienze, 99. § J. R. 



