76 



Larrimer (W. H.) & Ford (A. L.). U.S. Bur. Entom. The 

 Migration of HarmoUta grandis Form minutum : an important 

 Factor in its Control. — Jl. Econ. Entom., Concord, N. H., xii, no. 6, 

 December 1919, pp. 417-425, 1 plate, 3 figs. 



Recent observations show that the first generation of the wheat 

 pest, HarmoUta grandis, which is wingless, does not travel very far 

 from its place of hibernation in standing stubble. Infestation by 

 this Chalcid in fields adjacent to such stubble was found to vary 

 from 12'1 per cent, at the edge to OlO per cent, at a distance of 90 

 yards. As the infestation is practically negligible beyond a radius 

 of 30 yards, wheat planted at this distance from stubble or self-sown 

 wheat will be fairly safe from attack. If the first generation is thus 

 deprived of its natural breeding-places it will obviously mean great 

 reduction in the amount of infestation later in the season. All self- 

 sown wheat, especially that growing in stubble, should be destroyed 

 as it provides a breeding-place from which the second generation, 

 which can fly strongly, will infest the adjacent and neighbouring fields, 

 such infestation amounting to 6 '4 per cent, having been noticed at a 

 distance of 150 yards. 



MozNETTE (G. F.). U.S. Bur. Entom. Notes on the Bronze Apple- 

 Tree Weevil. — Jl. Econ. Entom., Concord, N. H., xii, no. 6, 

 December 1919, pp. 426-429, 1 plate. 



The bronze apple-tree weevil, Magdalis aenescens, Lee, has been 

 very prevalent in Oregon. It was found on apple, Crataegus and 

 Italian prune trees, but all trees attacked were either devitalised 

 or dying. The roughened portion of the bark is chosen by the female 

 for oviposition in preference to the smooth parts. Eggs were deposited 

 about 26th April in cavities excavated under the bark and the cavity was 

 sealed with frass. These eggs hatched on 14th and 15th May. The 

 larvae burrow immediately into the bark in any direction, and may 

 include a little of the wood in their tunnel. The tunnels are very small, 

 measuring about | mm. at first and about 2 mm. when completed. 

 The larvae continue feeding on the bark and surface-wood during 

 the winter, and in the spring an oval cell is excavated at the end of 

 the burrow between the bark and wood in which pupation occurs 

 about the beginning of April. The larval period lasts ten to eleven 

 months. The duration of the pupal stage depends on weather con- 

 ditions. The adults usually emerge about five days after pupation 

 and feed on the foliage, especially the upper surface of the leaves, 

 into Avhich they eat peculiar round holes. The adult life is brief. 



About 50 per cent, of this pest was apparently attacked by 

 parasites, including Tetrastichus sp. and a Braconid, Calyptus sp. 



Robinson (R. H.). The Beneficial Action of Lime in Lime Sulfur 

 and Lead Arsenate Combination Spray. — Jl. Econ. Entom., 

 Concord, N. H., xii, no. 6, December 1919, pp. 429-433. 



Experiments made with combined sprays show that greater decom- 

 position takes place when lime-sulphur is mixed with lead hydrogen 

 arsenate than with neutral arsenate. The efficiency of the spray is 

 decreased by about 35 per cent, and severe scorching may occur 



