118 



THE HOP. 



fly from the plum by common instinct to the nearest 

 hop plants. Here they settle, immediately insert their 

 beaks, and begin sucking up the sap of the plant, within 

 a few hours giving birth to another generation of liv- 

 ing young, which reach full growth without acquiring 



wings, just as did the first and second generations. 

 There now ensue between the middle of June and the 

 autumn, when the hop picking commences, from two 

 to eight additional generations of these wingless virgin 

 females, 



