GALL-FLIES. 377 



cracks or pores, however, are not large enough to 

 admit a human hair. But this, so far from being a 

 defect in the glutinous pclhcle of the bedeguar fly, 

 is, as we shall presently see, of great utility. The 

 sap which issues from each of those pores, instead of 

 being evaporated and lost, shoots out into a reddish- 

 coloured, fibrous bristle. 



One of the hristles of the Bedeguar of the rose magnified. 



It is about half an inch long, and, from the natural 

 tendency of the sap of the rose tree to form prickles, 

 these are all over studded with weak pricklets. The 

 bedeguar, accordingly, when fully formed, has some 

 resemblance, at a httle distance, to a tuft of reddish- 

 brown hair or moss, stuck upon the branch. Some- 

 times this tuft is as large as a small apple, and of a 

 rounded, but irregular shape; at other times it is 

 smaller, and in one instance mentioned by Reau- 

 mur, only a single egg had been laid on a rose leaf, 

 and consequently, only one tuft was produced. 

 Each member of the congeries is furnished with its 

 own tuft of bristles, arising from the little hollow 

 globe in which the egg or the grub is lodged. 



The prospective wisdom of this curious structure 

 is admirable. The bedeguar grubs live in their cells 

 through the winter, and as their domicile is usually 

 on one of the highest branches, it must be exposed 

 to every severity of the weather. But the close, non- 

 conducting, warm, mossy collection of bristles with 

 which it is surrounded, forms for the soft, tender 

 grubs a snug protection against the winter's cold, till, 



VOL IV. 32* 



