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The manner of dispersal of Phylloxera may be either natural or 

 artificiaL Natural dispersal is caused by winged forms, newly- 

 hatched examples which may or may not emerge from the soil, or 

 neogallicolae. The winged form may be neglected when European 

 vines are considered [see this Revietv, Ser. A, iii, p. 765]. The migration 

 of newly-hatched forms which emerge from the soil explains the 

 occurrence of new outbreaks at a greater or less distance from larger 

 centres. With regard to distribution by gallicolae, it is pointed out 

 that galls spread easily between closely-set vines, either actively, if 

 the branches interlace, or by means of the wind, which carries away 

 the neogallicolae-gallicolae when the latter are searching for a suitable 

 place for fixation. The neogallicolae-radicolae drop to the ground 

 and behave in a manner similar to the neoradicolae which emerge 

 from the soil. In slightly infested regions the appearance of galls 

 may contribute to the spread, but in districts which are severely 

 attacked the effect of the galls cannot be compared with that of the 

 neoradicolae. 



Artificial means of dispersal are the following : — (1) earth adhering 

 to the boots, etc, of labourers ; (2) birds, especially fowls, sheep, pigs, 

 etc., which may carry earth infested by Phylloxera ; (3) agricultural 

 implements ; (4) plants growing between the vines or used as props ; 

 (5) manure ; (6) water-courses ; (7) vine-cuttings ; (8) rooted plants. 

 The insect cannot survive over-night, except on very damp clothes ; 

 in the cool, damp days of spring and autumn they may survive long 

 enough to be carried to an immune vine if occasion offers. Implements 

 such as spades, etc., rarely carry the insect for any distance, owing 

 to the clean state in which they are kept by the peasants. The plough 

 is important as a means of dispersal, since it carries infected roots for 

 some distance and may drop them near clean plants. Labourers 

 while at work, often wear old boots with broken soles in which damp 

 earth may collect and where migrating individuals may live for several 

 days. Potatoes planted between the vines apparently do not aid 

 in dispersal. Rain, if accompanied by strong winds, undoubtedly 

 carries infected soil, newly-hatched forms, leaves bearing galls, etc., 

 into clean vineyards. On hilly ground, dispersion is effected by torrents 

 or streams. Vine-cuttings do not appear to harbour either winter- 

 eggs or hibernating insects, nor do rootlets given off from the shoots 

 of American vines seem to be a source of danger. Rooted plants 

 may introduce the insect into hitherto clean zones and have been the 

 cause of the destruction of the finest Italian vineyards. 



The methods of control proposed differ considerably from those 

 previously followed. It is suggested that the vine-growing parts of 

 Italy be divided into suitable districts, in which the cultivators, working 

 under an expert, take the necessary steps to prevent the introduction 

 of Phylloxera or prevent its spread if the vineyards are slightly infested. 

 At the same time, the reconstitution of vineyards should be effected. 

 Inspection should be carried out personally by the grower, and such 

 inspection should be avoided on damp, windy days. The production 

 of superficial roots should be reduced wherever Phylloxera exists or is 

 suspected of existing. The chief object should be the discovery and 

 prevention of spreading of new outbreaks. Efforts in the second of 

 these directions should be preceded by watering the ground with 

 a 1-2 per cent, solution of creoline on the previous evening. This 



