OVER THE HILLS AND FAR AWAY 13 



Hoppers) distantly related to Cicadas. One of the 

 commonest is called Aphrophora spumaria, and we see 

 it when we brush aside the froth with our finger. It is 

 a greenish creature with a rather squat body, on the 

 under side of which posteriorly there is a middle 

 groove which is used in a curious way in capturing air. 

 Briefly told, the story is this : The young Frog-Hopper 

 pierces the skin of plants with a proboscis enclosing 

 sharp needles ; it sucks up the sweet sap and it takes so 

 much that it overflows with it; it works its posterior 

 body up and down and with the help of the posterior 

 groove whips the sugary sap into a foam, just as the 

 cook beats up white of egg by entangling air in it with 

 a knife. At the same time it secretes a little wax from 

 glands near its tail. Now the watery, sugary sap, which 

 has passed through the Frog-Hopper's food-canal 

 and brought a ferment with it, makes when it is mixed 

 up with the wax a kind of soap, and when this is mixed 

 up with air it makes bubbles. Thus the young frog- 

 hopper is hidden amidst its own soap-bubbles; it is 

 kept moist during the heat of the day; and it seems 

 safe from almost all interference. After it has attained 

 its full size it leaves the froth as a winged insect able 

 to take big jumps among the herbage, and it is to this, 

 of course, that the word " frog-hopper " refers. When 

 the change to the full-grown form is accomplished 

 there is no more blowing of soap-bubbles ; and we can 

 understand, therefore, why we see less and less cuckoo- 

 spit as the summer goes on. We have not been able 

 to do more than outline the story, but surely we have 

 said enough to show that a very common thing, which 

 people who do not know any Natural History some- 

 times look at with real or pretended disgust, may have 



