151 



in 1912. Lygaeonematus laricis, Htg., occurred in great numbers on 

 young larches. Larvae, probably those of L. compressicornis, F., 

 were found on young aspen. Pristiphora pallipes, Lep. {apjjendi- 

 ■culata, Lep.), probably a common species on gooseberry, was only 

 reported from three localities. Arge rosae, L., injured roses though 

 it only attacked Liberty and to a smaller extent Caroline Testout, 

 other varieties escaping injury. Acantholyda kieroglyphica, Christ, 

 injured young pine trees at the end of July and the beginning of 

 August in several localities in the north of Sweden. A. stellata injured 

 2-year-old pine trees. 



Myriopoda. Blaniulus guttulatus, Gerv., has been reported injuring 

 the seeds of beans, peas and pumpkins, and Polydesmus complanatus, 

 L., damaged ornamental plants. 



Acari. Paratetranychus ununguis, Jac, attacked young spruce trees, 

 but the majority of the reports concerning spinning mites record 

 injuries caused in hothouses by P. althaeae, v. Hanst. ; P. pilosus, 

 C. & F., occurs commonly on apple and plum trees ; Tetranychus 

 telarius, L., attacked elms ; Bryobia praetiosa, Koch, injured goose- 

 berries in some localities. The following mites were also recorded : 

 Tarsoiiemus spirifex, March., on oats ; Pediculoides graminum, Reut., 

 on timothy and other grasses; Rhizoglyphus echinopus, F. & R., on 

 oats, barley and wheat ; Eriophyes pyri, Pgst., on pear; E. malinus, 

 Nal., E. similis, Nal., E. ribis, Xal., and E. vitis, Nal. 



Akerman (A.). Nagra iakttagelser rorande Harjningar av Vetemygg- 

 larver a Hostvetet Sommaren 1916. [vSonie Observations on 

 the Injury caused by the Wheat Midge {Contarinia triiici, Kirby) 

 on Autumn Wheat in the Summer of 1916.] — Svenska Utsades- 

 foreningens Tidshrift, arg. xxvii, h. 1, 1917, pp. 24-33. 



Contarinia tritici is one of the most injurious pests of wheat in 

 Sweden, often reducing the crojj by 5-10 pei cent, and sometimes, 

 as in Gotland, destroying about 66 per cent, of the grain. At Svalov, 

 where the present observations were made, serious damage was done 

 in the years 1901, 1903, 1905, 1912 and 1916, especially during the 

 last, when not only autumn wheat but also spring wheat and barley 

 were attacked. The investigations were conducted with a view to 

 obtaining reliable records of the extent of the injury caused to the 

 different varieties of wheat. 



0\^positing females were observed for the first time on the 24th of 

 June ; o\aposition continued for a comparatively long time, egg- 

 laying females occurring as late as on the 11th of July. The first 

 larvae were found in the middle of July, and at the end of the same 

 month they occurred in such numbers on the varieties most injured 

 that the ears were yellow. The examination of the different varieties 

 showed that the loss of grain varied between 2 '2 and 33 per cent., 

 the earlier varieties being most injured, this being due to the fact 

 that their ears emerged exactly at the time when the greatest number 

 of midges occurred. Varieties in which the ears emerged later were 

 far less damaged. The varieties most injured had pubescent ears, 

 and this seemed to justify the conclusion that these forms were more 

 exposed to attack than those with glabrous ears. This, however, on 

 further investigation was found not to be the case. The protection 



