ll>20] ECONOMIC ZOOLOGY — ENTOMOLOGY. 659 



General preventive measures are indicated, as venlilatiuii by cutting out and 

 l)runing in case of closely planted estates. 



An account is given briefly of attempts to present short courses for the 

 tniiiiiiig of youn.;; planters in dealing with plant diseases in this region. 



Hrown bast of Ilevea brasiliensis, R. D. Rands (Arch. Rubbcrcult. Neder- 

 lund. Indir, 3 {1919), Xo. 3, pp. 156, 157; Eng. cd., pp. 158, 159).— In a prelimi- 

 nary conmiunication including a short list of related publications, it is claimed 

 that brown bast presents a condition of severe gum formation apparently 

 arising as a reaction of the tree against the injurious form of tapping employed. 



The cause of brown bast in Hevea brasiliensis, W. Bobilioff {Arch. Rub- 

 bercidt. Ncdcrland. Indie, 3 (1919), No. Jf, pp. 172-178).— The cause of brown 

 l)ast is declared to be physiological. It is characterized by the formation of a 

 brown degenerate substance in the intercellular spaces and middle himellje of 

 the cortical cells. This substance gives the principal reactions for lignin. It 

 has not yet been proved that this substance is gum. Other characteristics are 

 the formation of burs and abnormalities of the stone cells. The severity of 

 the disease probably depends upon tho general phy.siologieal condition of the 

 trees. 



A method of steam sterilization of soil for controlling nematodes, L. E. 

 Mklchkrs {Phytopathology, 9 {1919), No. 7, pp. 29Jf-296). — A description is 

 given of a method used in 15 greenhouses at Hutchinson, Kans., in which low- 

 pressure steam was utilized for the control of nematodes {Ucterodcra radici- 

 cula). 



ECONOMIC ZOOLOGY— ENTOMOLOGY. 



Birds beneficial to agriculture, F. "VV. Fbohawk {Brit. Mns. {Nat. Hist.), 

 Econ. Ser., No. 9 {1919), pp. 17+47, pis. 22). — This consists of brief popular 

 accounts of the beneficial species occurring in Great Britain. 



Description of a new clapper rail from Florida, H. C. Oberholsee {Proc. 

 Biol. Soc. Wash., 33 {1920), pp. 33, S-i). 



Insects of economic importance, G. W. Herrick {New York: The Mac- 

 millan Co., 1920, rev. ed., pp. [6^+172). — This is a revised edition of the au- 

 thor's lectures in economic entomology, previously noted (E. S. R., 34, p. 651). 



Entomological work, W. G. Taggart {Louisiana Stas. Rpt. 1919, pp. 24- 

 26). — This report relates to investigations of the sugar cane moth borer in 

 cooperation with the Bureau of Entomology, U. S. Department of Agriculture, 

 a i)ulletin relating to which has been noted (E. S. R., 41, p. 60). Reference is 

 made particularly to the introduction of the tachinid fly parasite from Cuba, 

 and its establishment in Louisiana. 



Fungus insects and their hosts, H. B. Weiss and E. West {Proc. Biol. Soc. 

 Wash., 33 {1920), pp. 19, pi. 1). — This paper, which lists the fungus hosts of 

 in.sects, includes both in.sect and host lists. 



[Insect enemies of the loganberry], W. S. Bkown {Better Fruit, 14 {1920), 

 No. 10, p. 34)- — The ra.spberry cane maggot, the leaf hopper, and the raspberry 

 root borer are said to cause the most injury to the loganberi'y in Oregon. 



Text-book of protozoology, F. Doflein {Lchrbuch der Protozoenlcunde. 

 Jena: Gmlav Fischer, 1916, 4. cd., enh, pp. XV+1192, figs. 1201).— A new and 

 enlarged etlition of the work previously noted (E. S. R., 27, p. 356). 



Biologicul control of mealybugs in California, H. S. Smith and H. M. 

 Abmitage (Mo. Bid. Dept. Agr. Calif., 9 (1920), No. 4, pp. 104-158, pi. 1, figs. 

 S4)- — This Is an acc(mnt of the mealybugs attacking citrus in California (pp. 

 107-113), their natural enemies (pp. 114-118), the biological method (pp. 

 119-122), practical application of biological control (pp. 123-145), branch in- 



