252 



THE BLACKTHORN. 



egg, and continues her work on the stalk, either 

 until the plum falls to the ground by its own 

 weight, or it is left suspended by so fine a thread 

 that the first violent wind completely separates it 

 from the tree. This operation occupies two or 

 three hours, and is repeated until all her eggs are 

 laid, one only being intrusted to each plum. In 

 the course of a few days, if the weather be favour- 

 able, the larva is hatched, and immediately begins 

 to devour the pulp with which it is enveloped, en- 

 larging its mansion in proportion to its growth. 

 In five or six weeks it attains its full size, and 

 having by this time demolished all of its habita- 

 tion except the walls, eats its way out, and buries 

 itself in the ground, where it forms a new habita- 

 tion, and awaits its transformation. In the follow- 

 ing spring it appears as a beetle, and in its turn 

 begins the work of destruction. Immoderately 

 wet or dry weather is equally prejudicial to its 

 attaining the perfect state. If wet weather sets in, 

 the plum soon becomes rotten and unfit for its use ; 

 and if dry, warm weather sets in, and the half- 

 grown plum and egg shrivel together. The ex- 

 cessive increase of these pernicious insects may be 

 best checked by violently shaking the trees which 

 appear to be prematurely shedding their fruit, and 

 destroying all which fall to the ground. 



Another insect which occasions the fall of the 

 plum in its early stage is the Plum Saw-fly, {Ten- 

 thredo morio). Seen at a little distance, it resem- 

 bles a house-fly, but is strikingly distinguished by 

 having four wings instead of two. The head and 

 body are black, and the feet of a reddish yellow : 

 it is not likely to be confounded with any other 

 insect, as it is the only fly with feet of the same 



