226 The Natural History 



the female cocci are stationary, and seldom remove from 

 the place to which they stick, yet the male is a winged 

 insect ; and that the black dust which I saw was 

 undoubtedly the excrement of the females, which is 

 eaten by ants as well as flies. Though the utmost 

 severity of our winter did not destroy these insects, yet 

 the attention of the gardener in a summer or two has 

 entirely relieved my vine from this filthy annoyance. 



As we have remarked above that insects are often 

 conveyed from one country to another in a very 

 unaccountable manner, I shall here mention an 

 emigration of small aphides, which was observed in the 

 village of Selborne no longer ago than August the 

 ist, 1785. 



At about three o'clock in the afternoon of that day, 

 which was very hot, the people of this village were 

 surprised by a shower of aphides, or smother-flies, which 

 fell in these parts. Those that were walking in the 

 street at that juncture found themselves covered with 

 these insects, which settled also on the hedges and 

 gardens, blackening all the vegetables where they 

 alighted. My annuals were discoloured with them, and 

 the stalks of a bed of onions were quite coated over for 

 six days after. These armies were then, no doubt, in a 

 state of emigration, and shifting their quarters ; and 

 might have come, as far as we know, from the great hop- 

 plantations of Kent or Sussex, the wind being all that 

 day in the easterly quarter. They were observed at the 

 same time in great clouds about Farnham, and all along 

 the vale from Farnham to Alton.^ 



1 For various methods by wliich several insects shift their 

 quarters, see Derham's Physico- Theology. 



