SECT. III. THE BRANCH. 270 



bunches of the stem,, by some obstruction in the 

 channel of the sap or proper juice. A peculiar sort With 

 of knot or bunch is also often formed on the bunches.* 

 branches of the Dog-rose (PL IX. Fig. 9). The 

 nucleus, which is generally from an inch to an inch 

 and a half in diameter, is covered with a long and 

 winged shag, first of a green and then of a purple 

 colour, presenting the appearance of a small bunch 

 of moss. It has been occasioned like that of the 

 stem of the thistle, by the puncture of an insect 

 depositing its eggs in the tender shoot ; for if it is 

 cut open about the month of August, it contains 

 maggots. 



SECTION IV. 

 The Bud. 



THE regular developement of the bud is also Forming 

 often prevented by means of the puncture of in- 

 sects, and converted into a large globular tumor. - 

 This is very often effected by a species of Cynips 

 that lances its piercer into the heart of the bud 

 while yet tender, and penetrates with its saw into 

 the very pith ; injecting at the same time a drop of 

 the corroding liquor contained in its bag, and then 

 laying its egg. The bud being. thus wounded, and 

 the juices corrupted by the injected poison, the 

 circulation is not only impeded, but a fermentation 

 is induced which burns the contiguous parts and 

 changes their colour. The extravasated juice flow* 



