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attached to the ears and are to be found in the chaff, are those 

 of which the development has been arrested or which have been 

 attacked by parasites. De Meijere's statement has so far proved correct, 

 and no parasites were obtained from the larvae. Contarinia torquens, de 

 Meijere, distorts the hearts of cabbages, and it was observed at 

 Niedorp in North Holland that a field of cabbages which adjoined a 

 field of oats was heavily attacked in one part and remarkably healthy 

 in that part which was bordered by the oats. The shelter afforded 

 by the higher growing oats cannot be the explanation, because it 

 is precisely in such sheltered conditions that the trouble is greatest, 

 and the connection between the oats and the absence of the pest is 

 by no means clear ; the matter is being further studied. A species- 

 of Tijpula caused very serious damage to grass land in Oberijsel ; 

 the use of a very heavy roller at daybreak has proved more 

 or less effective, the larvae approaching the surface to feed at this 

 time of the day and being thus crushed. Eumerus lunulatus, Meig., 

 was found in potato pits in Pesse, but probably had been introduced, 

 possibly with onions, which it frequently attacks. A quantity of 

 hyacinth bulbs yielded larvae greatly resembUng those of Eumerus, 

 but an attempt to breed out the flies failed. Oscinella (Oscinis) frit, L.,. 

 was not nearly so destructive as in 1912, when oats, wheat and maize 

 suffered severely. Chortophila {Anthomyia) brassicae, Bouche, has been 

 found to play an important part in the spread of the " falhng sickness " 

 of cabbage, the imago distributing the spores of Phoma oleracea, Sace, 

 and the larva providing a means of entry for them ; direct damage 

 by the larvae was also extensive. Good results have been obtained 

 by the use of a solution of potassium permanganate, 1 in 2,000 of water, 

 against Psila rosae, L. ; the soil round the plants is first well wetted 

 and then a quantity of the solution is poured close round the root 

 collar. Against C. brassicae, collars of tarred paper seem still to be the 

 best remedy. A case of serious attack by aphids on seed-potatoes, 

 which were being sprouted in a cellar, was reported. The owner was 

 advised to expose them to the vapour of carbon bisulphide. Tulip 

 bulbs, which were beginning to sprout, were found to be heavily 

 infested by an aphid, possibly Aj)his tulipae, Boyer ; the same 

 treatment was successfully used. Schizoyieura [Tetraneura) ulmi, 

 de Geer, was found on the upper surface of elm leaves. The stem- 

 mother of S. ulmi hatches from a hibernated egg and produces about 

 40 young, which live in the protecting gall ; this breaks open in June 

 and the stem-mother dies and the young, after several moults, acquire 

 wings and migrate to various grasses, especially oats and wheat ; 

 this winged generation produces wingless young, parthenogenetically, 

 and these descend to the roots ; the progeny (sexuparae) of these are 

 again winged when fully grown and return in August to elms, where 

 they lay large female and small male eggs. The fertihsed females lay 

 only one egg, which lies the whole winter under the dried-up body 

 of the parent in a crack in the bark and the cycle begins again. The 

 life-cycle of Schizoneura {Tetraneura) pallida, Halid., is probably 

 similar, but the intermediate host plant is Mentha arvensis. Winter 

 spraying with 6 per cent, carbolineum is recommended. Schizoneura 

 ulmi, L. (fodiens, Buckt.), rolls up and causes the withering of the 

 edges of elm leaves. In the " exsulans " stage it lives on the roots of 

 currant bushes and has thus long been known as ;S. grossulariae, Schule 



