454 EXPERIMENT STATION EECOED. 



The enemies of Populus canadensis, P. Voglino (Ann. R. Accad. Agr. 

 Torino, 53 (1910), pp. S15-Wh flos. 16). — The first part of this paper (pp. r.25- 

 377) deals with the vegetable enemies, the second part (pp. 378-440) witr. the 

 insect enemies, of which 45 species are considered. 



The tarbagans and the plague, L. J. Tchaoushov (Vrach [St. Pete'Sb.], 

 1911, No. 24-25; ahs. in Off. Internat. Hyg. Puh. [Paris], Bui. Mens., 3 (1911), 

 No. 9, pp. 1626-1G30). — This paper on Arctoitiys bobac deals with its distribu- 

 tion, habits, and diseases, especially in its relation to plague. 



Termites and li-^nng plants, J. Chaine (Compt. Rend. Soc. Biol. [Paris], 11 

 (1911), No. 36, pp. 678-680; 72 (1912), No. 3, i)p. 113-115).— These, the sixth 

 and seventh papers (E. S. R., 24, p. 753) on the subject,, deal with the protec- 

 tion of plants from termites. 



New genera and species of North American Thysanoptera from the South 

 and West, J. D. Hood (Proc. Biol. Soc. Wash., 25 (1912), pp. 61-75, pi. 1, 

 figs. 6). — The forms here described as new are Stomatothrips flavus n. g. and 

 n. sp., from Monterey, Mexico ; Bregmatothrips venustus n. g. and n. sp., Haplo- 

 thrips graminis n. sp., and Scopasothrips unicolor n. g. and n. sp., all 3 taken 

 at Brownsville, Tex. ; RJiopalothrips bicolor n. g. and n. sp., taken on Opuntia,, 

 near Monterey, Mexico ; and Liothrips varicornis n. sp., swept from grass and 

 weeds at ilonterey, Mexico. 



Instructions for the destruction of locusts (Instrucciones para-la Destruc- 

 cion de la Langosta. Buenos Aires: Govt., 1910, pp. 60, figs. 25). — This paper 

 gives detailed information on the destruction of locusts in Argentina. 



The hemipterous enemies of cotton in Africa, H. Schouteden (Rev. Zool. 

 Afric. [Brussels], 1 (1912), No. 3, pp. 297-321, pis. 2, figs. i2).— The cotton 

 insect pests here considered are the cimicid Calidea apicalis, the coreid Lepto- 

 glossus membratiaceus, several species of Dysdercus, 4 species of Oxycarenus, 

 several plant lice of the genus Aphis, and the coccids Pseudococcus (Dactylo- 

 pins) pemiciosus and Chionaspis aspidistrw gossypH. 



Recent studies on the spontaneous distribution of phylloxera, B. Geassi 

 and M. Topi (Atti R. Acad. Lincei, Rend. CI. Sci. Fis., Mat. e Nat., 5. ser., 20 

 (1911), II, No. 11, pp. 603-611; ahs. in Internat. Inst. Agr. [Rome], Bui. Bur. 

 Agr. Intel, and Plant Diseases, 3 (1912), No. 2, p. 574)- — The following con- 

 clusions have been drawn by the authors: 



" It is wholly unlikely that phylloxera can, in compact earth not fissured or 

 mined, affect its spread through the earth without returning to the surface, and 

 thus infecting the roots of other vines The infiuence of light on the direction of 

 the path of the new born phylloxera insect is beyond doubt ; it is attracted by 

 light as certain motbs by the lamp. 



" It is likewise beyond doubt, on the other hand, that the new born phylloxera 

 insects can attach themselves and grow without ever having seen the light, 

 taking up their abode on the same root on which they are born (after returning 

 to it, should they happen to have left it). Or they may pass to the other roots, 

 of the same or different vines, either in contact with or quite close to the first, 

 traversing the fissures in the soil, the galleries burrowed by animals, the cavi- 

 ties formed by the working of the soil, by decomposition, by putrefaction of 

 organic substances, etc. 



" It is not in the like degree certain, but is nevertheless probable, that the 

 new born phylloxera insect reaches the surface whenever attracted there by a 

 little light through the soil ; thus the insect obeys the influence of positive photo- 

 tropism to which it is certainly subject, independently of the quality and quan- 

 tity of the food it finds available. Probably, once it has reached the surface, 

 the insect does not descend again until after night has set in." 



