INJURING THE ROOT. 113 



the surface. At the same time it is able, in the 

 winged condition, to migrate to more distant points. 

 The winged females, as before stated, begin to appear 

 in July, and continue to issue from the ground until 

 vine growth ceases in the fall. Yet they are much 

 more abundant in August than during any other 

 month, and on certain days may be said to literally 

 swarm. Every piece of a root a few inches long, and 

 having rootlets, taken from an infested vine at this 

 season, will present a goodly proportion of pupae ; 

 and an ordinary quart preserve jar, filled with such 

 roots and tightly closed, will furnish daily, for two 

 or three weeks, a dozen or more of the winged 

 females, which gather on the sides of the jar toward 

 the light. We may get some idea, from this fact, of 

 the immense numbers that disappear through the 

 air to new fields, from a single acre of infested vines, 

 in the course of the late summer and fall months. 

 If to the above account we add that occasionally 

 individuals abandon their normal underground 

 habit, and form galls upon the leaves of certain va- 

 rieties of grape-vine we have, in a general way, the 

 whole natural history of the species.' 5 



Remedies. — In America comparatively little has 

 been done in a practical way in fighting this insect, 

 because its injuries here are usually not serious. But 

 in Europe a great deal has been accomplished in 

 preventing its injuries. According to Dr. Riley the 

 means employed there "consist in (1) methods which 

 avoid the necessity of direct treatment, comprising 



