124 FRUIT CULTURE UNDER GLASS. 



carefully laid some pieces of vine-cane infested ■with, wingless 

 pucerons. I placed a handglass over each cane, and slightly 

 raised the glass on one side in order to allow the insect to creep 

 out. At three centimetres' distance from the pieces of cane I put 

 some fragments of root from a healthy vine, on which I had made 

 fresh wounds. In twelve hours the following results were 

 obtained : Three pucerons had found their way from one of 

 the vine-canes to the nearest piece of vine-root. Some days 

 after, twenty yovcRg pucerons occupied the same fragment. A few 

 insects were to be found on the other fragments. One piece of 

 root had attracted none, but the vine-cane nearest to it had very 

 few insects upon it which were capable of changing their places. 



"A similar experiment has been made by M. Fr^d&ic Leydier at 

 the farm of Lancieux, near Sigondas (a part of the country already 

 infested by the Phylloxera), and by another person near Sorgues. 

 The results of these experiments have not been satisfactory ; but 

 this does not prove that, under other conditions, or with a greater 

 amount of perseverance, they might not have been successful. It 

 is fortunate that this new enemy to the vine attacks it (in the 

 first instance) at the base of the stem, and not underground at the 

 fibres. As it is, a thorough dressing of the bottom of the stem 

 with coal-tar will probably prove an insurmountable obstacle to 

 the progress of this destructive insect ; but were the case other- 

 wise, it would be very difficult to get down deep enough to reach 

 an enemy so well protected by the depth of the soU." 



Eegarding the appearance of the insect, and the rapidity 

 with which it multiplies and devours its prey, this 

 writer's observations are correct; but I differ to some 

 extent on what the writer propounds as to its mode 

 of attack. 1 refer to [the article in question for the 

 entomology of this little devourer, and will now detail 

 some of my observations as to its effects, its mode of 

 attack, and circumstances which favour its spread, &c. 

 I may here state that not one of the observations to 

 which I refer has been intrusted only to one pair of eyes, 

 and that all that I wiU relate has been corroborated by 

 two and sometimes more observers. The insect is so 



