298 SMOTHER-FLIES. 



To this account I think proper to add, that, 

 though 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 de- 

 stroy 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 1st, 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*. 



* For various methods by which several insects shift their 

 quarters, see DERHAM'S Physico- Theology. 



