H^BEiRNAtiON 6F INSECTS. 433 



liiitclied in summer, usually fix them slightly to the 

 leaves upon which the larvae are to feed. But it is 

 evident that, were this plan to be adopted by those 

 whose eggs remain through the winter, their progeny 

 might be blown away along v-itli the leaf to which they 

 are attached, far from their destined food. These, 

 therefore, choose a more stable support, and carefully 

 fasten them, as has just been observed, either to the 

 trunk or branches of the tree, whose young leaves in 

 spring are to be the food of the excluded larvas. The 

 l&tter plan is followed by tlie female of Bornhj/x Neus' 

 tria, which curiously gums her eggs in bracelets round 

 the twigs of the hawthorn, &c. But another provi- 

 sion is demanded. Were these eggs of the usual deli- 

 cate consistence, and to be attached with the ordinary 

 slight gluten, they would have a poor chance of sur- 

 viving the storms of rain and snow and hail to which 

 for six or eight months they are exposed. They are 

 therefore covered with a shell much more hard and 

 thick than common ; packed as closely as possible to 

 each other ; and the interstices are filled up with a te- 

 nacious gum, which soon hardens the whole into a 

 solid mass almost capable of resisting a penknife. Thus 

 secured, they defy the elements, and brave the blasts 

 of winter uninjured. — The female of Bomhi/x dispar, 

 whose eggs have a more tender shell, glues them in 

 an oval mass to the stem of a tree (whence the German 

 gardeners call the larvae Stam-ruiipc), and then covers 

 them with a warm non-conducting coat of hairs pluck- 

 ed from her own body, equally impervious to cold 

 and wet. 



Another of those beautiful relations between objects 



VOL. II. 2 F 



