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without any visible cause. Hijdroecia micacea, at the beginning of 

 June, damaged rye at Malhng. Contarinia {Cecidomyia) tritici and 

 JSitodiplosis mosellana {Cecidomyia aurantiaca) did not do so much 

 harm as in 1912. An attack of Mayetiola {Cecidomyia) destructor 

 was recorded at Staevne at the beginning of July. Damage- caused 

 by Thysanoptera has been rather common, especially to rye. At 

 Aarhus, rye and wheat suffered somewhat from the Pentatomid, 

 Eurydeyna {Strachia) oleracea, which in that locality seems to develop 

 on Verba scum thapsus. Siphonophora cerealis and Aphis avenae 

 appeared at the end of June on oats and barley. Tarsonemns spirifex 

 is recorded from several localities, including Askow Experiment 

 Station, where, however, oats in well manured areas nearly escaped. 

 In northern Sleswick, as usual, the so-called Schlanstedt oats were 

 seriously damaged, while other varieties suffered less. As regards 

 the question of rotation, it has been observed that mixed crops nearly 

 always cause the mite to appear in oats following them. For this 

 reason, and owing to the presence of Heterodera schachtii var. avenae, 

 endeavours are being made to abolish the growing of mixed crops in 

 these places. 



Leguminous plants were attacked by the weevil, Sitones lineatus, 

 which was exceedingly common, especially at the end of April and 

 beginning of May, and in many places seriously injured vetches and 

 peas. At Thisted, the attack, which was very pronounced in May, 

 stopped owing to the rain. ApJiis rumicis {papaveris) at the end of 

 June made its appearance on horse-beans. At Lyngby, and possibly 

 also other places, aphids were checked in August partly by a parasitic 

 Hymenopteron, partly by the fungus Empmsa freseni, and had for the 

 most part succumbed when the rain set in. The caterpillars of Grapho- 

 litlia sp. in some localities destroyed 85 per cent, of the pods. Attacks 

 of Contarinia {Cecidomyia) pisi on the pods were not common, but 

 attacks of other gall-midges (not identified) on the flowers and 

 shoots of leguminous plants have occurred in several localities, as well 

 as serious damage caused by Kakothrips {Physapiis) rohustus. At the 

 Agricultural High School, Chortophila {Anthomyia) funesta attacked 

 lupins in July. 



Sugar-beet and beetroot pests included the larvae of Silpha opaca, 

 which are suspected of causing damage to sugar-beets in June and 

 the beginning of July all over the country. The plants become con- 

 stricted just below tiie surface of the ground, topple over and wither. 

 This happens however about three weeks after the injury, which 

 accounts for the larvae of the beetle being seldom found near the 

 injured plants. In some localities, injury caused by the larva of the 

 Noctuid, Hydroecia micacea, occurred. Serious attacks of Heterodera 

 schachtii were recorded from the South of Fyn and Lolland. The 

 beetle, Atomaria linearis, was only observed in one locality at Abed. 

 Aphis rumicis appeared on seed beets in the end of June, but 

 generally the attack culminated in the second half of July. It was 

 observed that aphids were spread in some cases by the wind. 



Turnips and cabbage were attacked by the maggots of Chortophila 

 (Anthotnyia) brassicae, which were very numerous in 1913, and from 

 June to late in the autumn caused great losses. In the north of 

 Sleswick, as early as the end of May, both young and full-grown larvae 

 and also eggs were found, the latter being in great numbers, attached 



