HISTORY OF INSECTS. 67 



annum ; and this amount, owing to unceasing 

 speculation, changes hands many times in the year. 



209. The principal hop counties in England 

 are Kent, Sussex, Surrey, Worcester, and Here- 

 ford. The hops grown at Farnham, in Surrey, 

 fetch the highest price. 



210. The hop-fly makes its first appearance in 

 May, generally about the 12th, and always be- 

 tween the 10th and 30th ; it is remarkable that 

 it mostly appears on the same day in all the hop 

 districts, however distant. 



211. The hop-fly makes its first appearance in 

 the winged state, a solitary fly being found settled 

 here and there on the under side of the young 

 leaves ; if the weather is warm, with mild rains 

 during the last twenty days of May, these flies 

 produce young ones, which are very small, and 

 are called deposit, or knits : these grow very fast, 

 and, in a few days, become green lice, which is 

 merely a larger form of the same animal. 



212. As soon as these creatures are born, they 

 insert their tube-like mouth into the leaf of the 

 hop, and begin sucking its sap : in this position 

 they remain fixed and stationary, daily increasing 

 in size for about ten days ; and then each indi- 

 vidual, without either love, courtship, or matri- 

 mony, begins bringing forth young ones, and 

 continues to do so at the rate of about eighteen 

 per day all the remainder of its life. 



213. The parent still continues growing; and 



r 2 



