292 FIELD, FOREST AND FARM 



eggs or birds' eggs would be good for nothing after 

 being left out-doors from autumn till spring. ' ' 



"That is true," assented Uncle Paul; "neverthe- 

 less these minute germs of future insect life seldom 

 fail to hatch when warm weather returns. From 

 them come plant-lice like those on the roots of the 

 vine. Each new-born louse crawls down the natal 

 vine, hunts around on the ground until it finds a 

 crack in the soil, and then makes its way through 

 this fissure to settle at last on a rootlet, into which 

 it plunges its sucker. At ease thenceforth beneath 

 the surface of the ground and in the bosom of abun- 

 dance, it does not long remain alone. Close to its 

 fixed position it deposits its little heap of yellow 

 eggs, whence there quickly issues a new generation. 

 In like manner each member of the family surrounds 

 itself with a family of its own ; and so on by several 

 successive repetitions of the process until, from hav- 

 ing but a single occupant at first, a root speedily be- 

 comes covered with a legion of destroyers. To this 

 population of recent origin we must not forget to 

 add the older inhabitants that have passed the win- 

 ter under ground and have only waited for the re- 

 turn of the warm season to resume their own laying 

 of eggs on the roots of the vine. 



"Let us recapitulate these singular ways of the 

 phylloxera. The species comprises three forms of 

 insects, each having its own peculiar structure, its 

 manner of life, its separate function. The custom- 

 ary animal unity is here a trinity : three different in- 

 sects are grouped in a single species. 



