421 



freshly uprooted poplar harboured 3 species : — a Cossid, a Buprestid and 

 the bark-beetle, Cnjphaliis asperatus. Bark-beetles, chiefly Hylesinus 

 crenutus and H.fraxini, also occasionally infested ash to a serious extent. 

 The differences in insect infestation in a virgin forest and in a 

 cultivated one are discussed, the conclusion reached being that in the 

 Bialowies forest injurious insects are of very little importance. Their 

 increase is checked by the mixture of plant species, by the vigour 

 of the trees due to growth in naturally suitable situations and to 

 natural re-afforestation, and by the abundance of natural enemies. 

 These findings point to the need for bringing cultural methods as much 

 as possible into line with the conditions found in nature. 



EscHERiCH (K.). Die Bekampfung schadlicher Insekten. — Frankfort 

 on Main, Werner u. Winter G. m. b. H., 1919, pp. 5-15, 3 plates 

 [Received 28th July 1920.] 



In this article the economic and hygienic necessity for combating 

 injurious insects is explained in simple language. 



CoELHO DE SouzA (W. W.). Combate a Lagarta rosea. [Work 

 against the Pink BoUworm.] — Brasil Agricola, Rio de Janeiro, 

 V, no. 1, January 1920, pp. 12-14, 1 fig. [Received 30th July 1920.] 



It is recommended that each of the more important townships in the 

 Brazilian cotton zone should be provided with a cotton-seed disinfecting 

 apparatus, one made in Rio de Janeiro being said to be suitable. A 

 furt.her measure against the pink bollworm [Platyedra gossypiella] is 

 crop rotation, and French beans should be planted in land where cotton 

 has been grown. 



Feytaud (J.). Sur les jeunes Colonies du Termite lucifuge. — C. R. 



hebdom. Acad. Sci., Paris, clxxi, no. 3, 19th July 1920, pp. 203-206. 



The founding of new colonies by the swarming of kings and queens 

 is an established fact in the case of Leucotermes lucifugus, Rossi, and 

 they can form colonies likely to live on freshly cut pine stumps. Two 

 years later most of these colonies still possess the royal pair in the midst 

 of a large population, in which the soldiers are relatively more numerous 

 than in the old colonies. Swarming takes place for the first time at 

 the end of the second year and is probably not repeated each spring. 

 The replacement of the royal pair begins before the end of the second 

 year. 



HoLLANDE (A. C.) & Vernier (P.). Coccohacillns insedorum, n. sp., 

 Variete malacosomae, Bacille pathogene du Sang de la Chenille 

 Malacosoma castrensis, L. — C. R. hebdom. Acad. Sci., Paris, 

 clxxi, no. 3, 19th July 1920, pp. 206-208. 



The blood of 50 per cent, of the caterpillars of Malacosoma castrensis, 

 L., feeding on the leaves of Poterivm sanguisorba in the neighbourhood 

 of Nancy was found to be infected with a new organism, Coccobacillus 

 insectonon var. malacosomae. Experiments showed that the cater- 

 pillars of 31. castrensis and of Vanessa urticae are killed in 24 hours by 

 an inject on of the Coccobacillus into the blood or by merely pouring 

 the culture on the leaves, while those of M. neustria die 12 hours after 

 the injection of the organism, although only 30-60 per cent, are killed 

 through the medium of the leaves. 



