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Froggatt (W. W.). Orchard and Garden Mites. No. 2.-Spinning 

 Mites (Family Tetranychidae). — Agric. Gaz. N.S.W., Sydney, 

 xxxii. no. 2, Febnuiry 1921, pp. 130-135, 3 figs. 



This article mentions several species of Tetranychids found in 

 various parts of the world and gives a short account of Tetranychus 

 ■telarius, L. (red spider), and Bryohia pratensis, Garm. (apple-stem 

 mite). In consequence of the long dry spring, the roses in suburban 

 igardens near Sydney were considerably injured by T. telarius in 1920. 

 On the stems of fruit trees in winter, the eggs and young mites can be 

 destroyed with lime-sulphur, and as this is a winter spray largely used 

 by commercial orchardists, this pest does not cause them very much 

 trouble. Dusting the infested foliage with flowers of sulphur is effective 

 on rose bushes and other small garden plants. 



Davidson (W. M.). U.S. Bur. Ent. Observations on Psyllohora 

 taedata, Le Conte, a Coccinellid attacking Mildews (Col.). — Ent. 

 News. Philadelphia, Pa., xxxii, no. 3, March 1921, pp. 83-89. 



Psyllohora taedata, a common Coccinellid in California, is found to 

 be associated in all stages with fungous infestations of the mildew type, 

 and it appears to be especially attracted to rose and apple powdery 

 mildew [Sphaerotheca pannosa and Podosphaera oxycanthae). The adult 

 beetles issue from hibernation in April, and breeding continues until 

 November or even December. In midsummer the life-cycle lasts 

 about a month, but varies very much according to the temperature, 

 so that there are probably not more than five generations a year. In 

 the field the eggs are always placed near a fungus infestation, and all 

 through their larval existence the insects under observation fed on the 

 fungi. On an average, the larval stage lasts about 19 days. P. taedata 

 has been reported as feeding on Aphids, red spiders {Tetranychus) 

 and scale-insects, but experimentally the larvae were found to starve 

 rather than partake of such animal foods. Similar results were 

 obtained with adult beetles, except that they can live for considerable 

 periods without food. The author suggests that the peculiar form of 

 the mandibles in this beetle may be an adaptation to assist the larvae 

 to grasp the tissues of the fungus. 



CouRTiNE (E.). A Propos des Vers Blancs dits a Hanneton. [Concern- 

 ing White Grubs said to be of Cockchafers.] — Rev. Agric. Afrique 

 du Nord, Algiers, xix, no. 84, 11th March 1921, pp. 198-199. 



A serious outbreak of Coleopterous larvae, thought to be those of 

 Rhizotrogus sp., over a large area sown with cereals is recorded. 



On a former occasion, in 1910, the grubs caused serious damage in the 

 year preceding their metamorphosis into adults, without anything being 

 done to check them, but in the following year, when the adults began to 

 emerge from the ground, hand-collection was tried and some 40 to 60 lb. 

 of the beetles were collected each evening, without apparently 

 diminishing their numbers to any great extent. A spray of \ lb. 

 sodium arsenite to 20 gals, of water was then applied to some 125 

 acres of cereals, hand-collection being stopped. After two or three days 

 no more beetles appeared, and the land treated has now been free from 

 white grubs for ten years. 



