HOP-FLY. 67 



burnt, not thrown on the ground, or else the blights 

 are sure to climb up the stalks again, and, stopping here 

 and there at the best landing-place, increase and multiply, 

 and soon cover the whole plant; nor should they be buried 

 in the ground, for the blights take care to outwit you by 

 living underground for months, and when the gardener's 

 spade turns them up again, they make for the beans direct- 

 ly : the plan of topping the beans does not injure the crop, 

 but, if carefully done, rather improves it. The blight of the 

 willow is very large, and, at first sight, looks grayish, but 

 under a glass is beautifully variegated with black and 

 white ; when crushed it gives out a deep, blood-coloured 

 dye, which stays on your hand several days in spite of fre- 

 quent washings. 



I have taken a good deal of pains to find out the birth 

 and parentage of true blights ; and for this purpose have 

 watched, day after day, the colonies of them in my own 

 garden, and single ones which I have kept in-doors, and 

 under tumblers turned upside down ; the increase is prodi- 

 gious ; it beats everything of the kind that I have ever 

 seen, heard, or read of. Insects in general come from an 

 egg, then turn to a caterpillar, which does nothing but 

 eat, then to a chrysalis, which does nothing but sleep, 

 then to a perfect beetle or fly, which does nothing but in- 

 crease its kind. But blights proceed altogether on another 

 system : the young ones are born exactly like the old 

 ones, but less ; they stick their beaks through the rind, 

 and begin drawing sap when only a day old, and go on 

 quietly sucking away for days; and then, all at once, 

 without love, courtship, or matrimony, each individual be- 

 gins bringing forth young ones, and continues to do so for 

 months, at the rate of from a dozen to eighteen every day, 



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