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Graf (J. E.) & Boyden (B. L.). Eradication of the Sweet-potato 

 Weevil in Florida (A Report of Progress). — U.S. Dept. Agric, 

 Washington. B.C., Dept. Cue. 201, 23rd November 1921, 13 pp., 

 2 figs. [Received 22nd March 1922.] 



The results of the work in Florida during the past three years on 

 the eradication of Cylas formicarius, F. (sweet potato weevil) are 

 given, as they prove that the same methods will be successful against 

 this pest in other localities where the abundance of wild food-plants 

 does not offer a fresh and continuous source of infestation. Careful 

 sorting of the crop, the use of clean planting stock and an annual 

 change of location for the main planting will reduce infestation to 

 a practically negligible quantity. 



Jegen (G.). Die Bekampfung der Obstbaumschadlinge im Winter. 



[Winter Measures against Fruit-tree Pests.] — Landw. Jahrb. 

 Schweiz, Berne, xxxvi, no. 1, 1922, pp. 83-101. 



Investigation has shown that the following fruit-tree pests hibernate 

 in orchards : Anthonomus pomorum ; Cydia pomonella ; various 

 bugs — Anthocoris, Calocoris, Aradus and Tingis ; and the flea- 

 beetles, Phyllotreta undulata, P. atra and P. nigripes. 



Parasitic Hymenoptera and Tachinids are comparatively rare on 

 the fruit trees in winter, so that the importance of winter measures 

 is enhanced. Such measures are the scraping of old, rough-barked 

 trees and the burning of the debris, coupled with the spraying of 

 the trees with milk of lime or with a 6-8 per cent, solution of soft 

 soap. The latter must always be used if the trees are infested with 

 woolly aphis [Eriosoma lanigeritm] in summer. 



Leefmans (S.). Bijdrage tot het Vraagstuk der Bladrollers van de 

 Thee. [A Contribution to the Question of the Leaf-rollers of 

 Tea.] — Meded. Inst. Plantenziekten, Buitenzorg, no. 51, 1921, 

 83 pp., 20 plates. (With a Summary in English.) [Received 

 22nd March 1922.] 



This paper deals principally with the biology of Cydia {Laspeyresia) 

 leucostoma, Meyr., and Gracilaria theivora, Wlsm. The tea tortrix, 

 Homona coffearia, Nietn., which is such an important pest in Ceylon, 

 is of far less consequence in Java than the other two moths. The 

 role played by these pests in British India and Ceylon is reviewed. 

 In Java 18 out of 94 estates reported important losses due to 

 G. theivora. On one the crop has been sometimes reduced to one- 

 half, or even lost altogether. In another instance 29 per cent, of the 

 leaves were attacked by G. theivora and 25-6 per cent, of the shoots 

 were spun together by C. leucostoma. The worst damage is done at 

 altitudes of 3,300-4,900 feet. Both species occur in Sumatra, but 

 no losses have been reported from there. Most of the injury is done 

 in the dry season, but attacks during the rains are not rare. Both 

 old and young plants are attacked. The severest infestation occurs 

 2-5 months after pruning. It is not clear whether forests near the 

 tea plantations have a bad effect on infestation. 



The eggs of G. theivora are laid separately, usually near the mid-rib 

 on the younger leaves. At the altitude of Buitenzorg (800 feet) the 

 egg-stage lasts 2-3 days. The larva bores through the leaf -epidermis 

 and begins mining the leaf-tissue. In old leaves it is unable to pierce 



(6551) Wt. P6/200 1500 6/22 Harrow G.75 1921 T 



