A NUMEROUS FAMILY 35 



astonishing rapidity when they multiplied it by two. 

 For the family of the plant-lice the increase is much 

 more rapid, as the multiplication is made by ten. 

 It is true that the calculation stops at the twelfth 

 instead of going on to the sixty-fourth. No matter, 

 the result would stupefy you ; it is equal to a hun- 

 dred thousand millions. To count a cod's eggs, one 

 by one, would take nearly a year; to count the de- 

 scendants of one plant-louse for six months would 

 take ten thousand years ! Where are the devourers 

 that would see the end of the miserable louse ? Guess 

 how much space these plant-lice w r ould cover, as 

 closely packed as they are on the elder branch." 



"Perhaps as large a place as our garden," sug- 

 gested Claire. 



"More than that; the garden is a hundred meters 

 long and the same in width. Well, the family of that 

 one plant-louse would cover a surface ten times 

 larger; that is to say, ten hectares. What do you 

 say to that? Is it not necessary that the young 

 birds, little lady-bugs, and the dragon-fly with the 

 golden eyes should work hard in the extermina- 

 tion of the louse, which if unhindered would in a 

 few years overrun the world? 



"In spite of the hungry ones which devour them, 

 the plant-lice seriously alarm mankind. Winged 

 plant-lice have been seen flying in clouds thick 

 enough to obscure the daylight. Their black legions 

 wmt from one canton to another, alighted on the 

 I'm it trees, and ravaged them. Ah ! when God wishes 

 t<> try us, the elements are not always unchained. 

 He sends against us in our pride the paltriest of 



