70 OF THE INSECT IN ANOTHER STAGE. 



in the same spot two maggots or grubs, about 

 half an inch long, of a whitish brown, and 

 dark heads, and likewise concealed very safely 

 between the rind and the wood, two insects in 

 a chrysalis, rather a lighter colour than those 

 from which the insects had flown, and I was 

 convinced from what I knew of natural history, 

 that these were all the same species of insect. 

 I then began to think that what produced the 

 canker, and the white blight, must be two 

 distinct species of insect ; but standing reflect- 

 ing on what I had seen, with a view to fur- 

 ther examination, I observed a strange look- 

 ing fly, about half an inch long to all appear- 

 ance, fly very deliberately from tree to tree, 

 I may say nearly twenty, and appeared to set- 

 tle near the bottom, but its wings were scarcely 

 quiet before it again took flight; and as it 

 stopped at every tree it came to, I watched it 

 very closely; at last it came to a tree which had 

 the canker very bad just at the graft: this tree 

 the fly took a fancy to, and having settled for 

 about two or three seconds, it did the same at 

 every knot it could find all up the stem ; after 

 it had settled six or eight times (during which 

 time it seemed very intent,) I knocked it down, 

 and taking it in my hand, and it not being dead, 

 I gave it a squeeze in the palm of my hand with 

 my thumb to kill it, which caused it to dis- 



