375 



formulae are given : 5 lb. soft-soap dissolved in 5 gals, hot water, 

 mixed with 6 lb. pyrethrum powder and diluted with 45 gals, of cold 

 water ; or, 50 gals, water containing 1 lb. olein soap and 5 lb. pyre- 

 thrum powder. Good quahty pyrethrum powder is, however, very 

 scarce at the present time, and it is doubtful whether it could be 

 obtained in sufficient quantities for large applications. The author 

 has recommended the culture of pyrethrum in France, which should be 

 successful, as it has been in Switzerland; but none has as yet been 

 gathered. Meanwhile, ni(;otine at 10 per cent, strength is recom- 

 mended at the rate of 1| gals, per 100 gals, of water. 



Oguma (K.). a New Scale-Insect, Xylococcus alni, on Alder, with 

 special reference to its Metamorphosis and Anatomy. — Jl. Coll. 

 Agric. Hokkaido Imp. Univ., Sapporo, Japan, viii, pt. 3, March 

 1919, pp. 77-109, 4 plates. [Received 7th July 1920.] 



Xylococcus alni, sp. n., here described, seems to be restricted to 

 Alnus japonica. It takes three years to reach maturity ; and all the 

 specimens that have been examined are in the same stage of develop- 

 ment, no case having been found in which examples of different stages 

 occur in one and the same yeaf . 



FuLLAWAY (D. T.). Division of Entomology. — Hawaian Forester and 

 Agricidturist, Honolulu, xvii, no. 5, May 1920, pp. 133-135. 



During 1919 no new field work was undertaken owing to the unsettled 

 conditions, but a pupal parasite of Pieris rapae (the imported cabbage 

 worm) obtained from Cahfornia was propagated in the insectary, and 

 large colonies were hberated in the cabbage fields in Oahu and Hawaii. 

 It.5 estabhshment has not yet been determined. 



Considerable time has been given to the study of termites, which 

 are becoming severely destructive wiih. the increase and spread of two 

 lately immigrant species. 



In September an infestation of forest ferns by the AustraHan fern 

 wee\^il, Syagrius fulvitarsis, was discovered [R.A.E., A, viii, 191]. 

 The ferns are important as part of the ground cover of the Hamakua 

 forest reserve, and it was decided to attempt to control the outbreak 

 and prevent its spread beyond the small area aUected. This necessi- 

 tated the destruction of all ferns in the area as far as possible, which 

 were cut and burned ; thereafter, the ground cover was either fired 

 or poisoned to destroy crawhng weevils, which might have escaped 

 the initial treatment, and every vestige of fern plant ; and an artificial 

 barrier of crude oil was laid to contain the insect. At fche same time 

 a study was made of the weevil's life-history. 



The following beneficial insects have been Hberated : — Galesus 

 silvestrii 7,710, Diachasma tryoni 12,465, D. fullawayi 2,325, Tetras- 

 tichus giffardianus 28,675, Dirhinus gijjardi 3,640 and Opius humilis 

 0,900, aU being parasites of the fruit-fly [Ceratitis capitata] ; Opius 

 Jletcheri 45,695, a parasite of the melon fly [Dacus cucurbitae] ; Parana- 

 grus osborni 154,200, a parasite of the corn leaf-hopper [Peregrinus 

 1 maidis] ; and Spalangia cameroni 7,300, and Pachycrepoideus didmis 

 L 150, parasites of the horn-fly [Lgperosia exigua]. 



