57 



not generally appear on Italian vines. The question therefore arises 

 as to the fate of the insects which, particularly in the infected 

 vineyards of Upper Italy, are produced in such great abundance. 

 Do the gallicolae, on leaving the winter egg and finding no vine suited 

 to the production of galls, disappear and die, or do they disperse 

 before laying eggs, or lay them promiscuously, so that the sexual 

 insects only meet wnth difi&culty ? As an experiment in this connection 

 two plants in a \'ineyard, one a Clinton and the other an Italian vine, 

 were covered over with a cage and many nymphs from infected vines 

 as well as winged forms were placed in them. In the follc^dng spring, 

 contrary to expectation, no galls had formed on either of the covered 

 trees. It is difficult to account for this absence of gallicola infection. 

 Apparently the Clinton variety, which is of uncertain origin, is incapable 

 of bearing galls and therefore on this plant the gallicolae that hatch 

 from the winter eggs are lost. It might also be assumed that to 

 produce the infection it is necessary not only that the plant should 

 be capable of producing galls, but that infection should first occur in 

 the roots, or that galls either from the same vine or from specified 

 vines should be used. This hypothesis would explain the experiments 

 already described and is supported by the fact that in the same \^ne- 

 yard, which had been almost totally destroyed by Phylloxera, there 

 was no sign of infection in the different varieties of wild American 

 v'ines present in it. If the American vines or the hybrids had had any 

 attraction for the winged insects, infection must have occurred. 



It is known that gallicola infection always appears in a country or 

 district after, even many years after, radicola infection. This may 

 possibly be explained by admitting the necessity for the passage of 

 infection through the roots of American vines. If these vines attract 

 winged insects of any origin, it would not be difficult to explain the 

 absence of galls in vineyards of stock plants of American vines bordering 

 on phylloxera-infected belts, as occurs in so many nurseries in Apulia. 



Theobald (F. V.). Poultry in Orchards and Their Effect on Injurious 

 Insects. — Reprint from Fruit, Flower & Vegetable Trades' Journal, 

 London, 13th October 1917, 2 pp. 



Fowls are of far more practical use than is generally supposed in 

 checking insect pests of fruit, and the trees both in grass-grown and 

 cultivated orchards where they are allowed to run are much healthier 

 for their presence. In spring and summer they destroy the caterpillars 

 of Cheimatohia brumata (winter moth) that come down to pupate in 

 June, as well as those that have been blown or washed off the trees ; 

 they also pick up the wingless females emerging from the ground in 

 autunm and winter and so stop the next year's attack. Larvae of 

 Cydia pomonella (codhng moth) are eagerly devoured, as also are those 

 of Eriocampoides (Eriocumpa) limacina (pear and cherry sawfly), 

 Chloroclystis {Eupithecia) rectangulata and many of the leaf-rolling 

 Tortricids, while Malacosoma (Clisiocampa) neustria (lackey moth) is 

 occasionally taken. Contarinia (Diplosis) pyrivora (pear midge) is 

 said to be controllable only by fowls kept under the trees through June 

 and into July. The cocoons of ants, particularly of Myrmica and 

 Lasius, are a favourite food, and thus Aphis malifoliae, which is 



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