ECONOMIC ZOOLOGY — ENTOMOLOGY. 661 



experimental evidence whatsoever tliat the disease may be air borne, as 

 claimed by Mr. Reiff, although of course we do not wish to exclude such a 

 possibility." 



The paper concludes with a brief description of the new organism, Qyrococeus 

 flaccidifex n. g. and n. sp. 



Studies of the wipfelkrankheit of the nonne moth, K. Escheeich and M. 

 MiYAJiMA (Nat uric. Ztschr. Forst u. Landw., 9 {1911), No. 9, pp. 381-/^02, figs. 

 6). — This article first briefly reviews the subject and discusses its diagnosis, then 

 reports observations and experiments on the transmissibility of the virus of 

 wilt disease in nun moth cateiTpiUfirs, the course of the disease, and nature of 

 the virus. 



The Mycetophilidae of North America, Part IV, O. A. Johannsen {Mame 

 Sta. Bill. 200, pp. 57-U6, pis. 7).— In this fourth paper (E. S. R., 27, p. 57) 

 the species of the remaining genera of the subfamily Mycetophilinse are char- 

 acterized together with those of the subfamily Sciariure. " The members of 

 the former so far as known injure mushrooms only; the latter constitute the 

 most important group so far as the agriculturist is concerned. 



" Though occasionally reported as injuring mushrooms the members of the 

 Sciarinas are not as a rule regarded as serious pests of the fleshy fungi, differ- 

 ing in this respect from the species of the other subfamilies. After partial 

 decay of fungus growths, however, larvae of Sciara are found in abundance, and 

 it is this fact which, in some cases at least, has led observers and growers to 

 attribute the destruction to these gnats when in all probability the injury was 

 caused by species of Mycetophila, Exechia, or Phorids. On the other hand 

 there is no laclv of evidence of the harmful character of some species of 

 Sciarinaj to seed corn, to potatoes, to wheat, and to the roots of other plants." 



The biology of the cockchafer (Terre Vaud., S (.1911), No. 50, pp. 453-455. 

 fig. 1; ahs. in Internat. Inst. Agr. [Rome], Bui. Bur. Agr. Intel, and Plant 

 Diseases, 3 (1912), No. 2, pp. 512-514) ■ — This paper presents a brief account of 

 work carried on by Decoppet, who has conducted studies at Farzin, in the Can- 

 ton of Vaud, Switzerland, in a region where the farm and forest injuries caused 

 by the pest are often very great, the roots and foliage of seedlings and trees 

 (pines, spruces, larches, and silver firs), grasses, and some field crops being 

 attacked. 



The action of carbon disulphid on cockchafer larvse and on the growth of 

 some forest trees, Decoppet (Bui. Soc. Vaud. Sci. Nat., 5. ser., 48 (1912), No. 

 176, pp. XXXV, XXXVI; ahs. in Internat. Inst. Agr. [Rome], Bui. Bur. Agr. 

 Intel, and Plant Diseases, 3 (1912), No. 6, pp. 1456, i^JT).— The author found 

 that carbon disulphid at the rate of from 1 to li oz. per square yard injected 

 into 6 or more holes considerably diminished the injury caused by white grubs. 

 In some of the experiments conducted the loss due to their attack in beds thus 

 treated was reduced to 1 or 2 per cent, although it amounted to 20 per cent at 

 the commencement and SO per cent in untreated beds. Carbon disulphid also 

 has a beneficial effect in stimulating the growth of vegetation. 



The author concludes that the " application of carbon disulphid should be- 

 come a regular practice in forest nurseries; it will not destroy all the white 

 grubs in the soil, but will greatly reduce their number, thus permitting the 

 plants to make new roots ; and owing to the effect of the disulphid, the absorp- 

 tion of assimilable substances in the soil is increased, as is shown by the in- 

 creased power of resistance possessed by the young trees. The disulphid must 

 be injected into the soil as uniformly as possible, at the rate of 1 to 1^ oz. per 

 square yard in 6 to 8 holes. Ground recently broken up should not be treated. 



