THE PHYLLOXERA 



bush, from garden to garden! By what means is 

 it able to spread in all directions without limit? 



"Let us examine a number of rosebushes, and we 

 shall have a prompt answer to our question. In ad- 

 dition to the wingless plant-lice, big of belly and all 

 grouped on the tender twigs, we shall see others, 

 green like the first ones, but more elegant in form, 

 of greater freedom of movement, and provided with 

 four wings, very beautiful wings too, diaphanous 

 and gleaming with rainbow tints. These creatures 

 are no lazy sap-bibbers forever squatting over the 

 well their sucker has bored. They are seen to come 

 and go, circulating briskly among the stationary 

 herd, inspecting the f oliage, passing from branch to 

 branch, and even taking flight for some distant goal. 

 They are the travelers of the family. Their func- 

 tion is to propagate the race in the surrounding dis- 

 trict, with the aid of their wings, and even at con- 

 siderable distances when a puff of wind carries them 

 thus far. 



"Two classes, then, dissimilar though related, are 

 to be noted among the green lice of the rosebush and 

 the black ones of the beanstalk, as also among count- 

 less others. The members of one class have no 

 wings ; they pass their lives where they were born, 

 and multiply in serried legions. Those of the other 

 class, which is relatively small, are equipped with 

 wings. Confined to no one spot, they fare forth as 

 some passing breeze or their own strength of wing 

 may determine, and deposit in favorable localities 

 the germs that are to serve each as the beginning of 



