DISEASES OF PLANTS, 545 



[19(X)), pp. 200-3Jf2, fig. I). — A inono},'rai)h on the caiiiitbor tree {Cinnainoiiium 

 <<ii>tiili</iii) and its i)r(Hlucts, from a historical, iiulustriaj, foniniorcial. and ciil- 

 niral standpoint, with spi'ciai rcfcronct' to tlic introdut-tion of caniplior t-ultiire 

 into Italy, to;:otlier with tahnlatod data relative to analytieal stndies of cani- 

 jihor extracted Ironi the leaves of trees growinj; in different parts of Italy. 



The work eonelndes with an extensive classified ]»il)lio<;raphy of the camphor 

 tree and its jiroducts. 



Rubber extraction (Lc Brisil: Scs I{ichcs)ics Xaturclles; ses Industries. 

 Rio (lc Janeiro: Centra Indus. Brasil, 1908, French ed., vol. 1, pp. 169-187). — A 

 ^'eneral account of the rubber industry in Brazil, includinfj the prevailing 

 methods of exploitation, varieties, and the important rubber-producing ref^ions, 

 together with considerable statistical data relative to itroduction, valuation, 

 and exports of rubber. 



Ecanda rubber (Raphionacme utilis), O. Staff {Roy. Hot. (lard. Kew, Bui. 

 Misc. Inform., JUOS, .\o. 5, pp. 209-215, pi. 1). — The author is of the opinion that 

 the tuberous rubber plant found in Portuguese West Africa and reported by 

 ('. E. de Mello Geraldes (E. S. R., 19, p. 345) is identical with specimens 

 later received at Kew both from West Africa and from Mozambique. The 

 important features of Professor Geraldes's account of this plant, including 

 extraction tests, are given, together with a preliminary botanical description 

 and a plate showing the si)eciuiens grown at Kew. 



The i»lant. which belongs to the genus Kaphionacme, of which about 20 

 species are l;nown, nearly all of them natives of tropical Africa south of the 

 «>quator, has been named R. utilis by Brown and Stapf. 



DISEASES OF PLANTS. 



Plant diseases in 1907, M. L. Mortensen, S. Rostrup, and F, K. Ravn 

 ( 7'iV/xvA/-. Ijtndbr. Planteavl, 15 (1908), .A'o. 1, pp. 1J{.5-1.5S). — A general survey 

 of diseases of agricultural crops in Denmark during the year. 



Trials with the hot-water treatment for six-rowed barley, F. K. Ravn 

 (Tidsskr. Lnndhr. I'lantearl, 15 (1908), Xo. 1, pp. 159-170).— VAther of the 

 following methods is reconnnended on the basis of the trials reported : Dipping 

 the grain 20 times during r» minutes in water at 50 to 57° C, and immediately 

 cooling it in the air; or soaking the grain in cold water for 3 hours, subse- 

 quj'iitly allowing the wet grain to stand for 10 hours, tlien dipping it 20 times 

 (luring 5 minutes in water at 50 to 52° C, and immediately cooling it in the 

 nir. The foinici- nictliod is to be preferred, as it gives the best gernunation of 

 the barley. It is inii)ortant in tliese treatments that the temi)erature be ke|"t 

 constant during the dipping, and tlnit tlie cooling be done at once; the latter 

 process is jireferably done in the air, rath«'r than by dipping in water. 



Wart disease, or black scab, of potatoes {.Jour. Ilnrt., GO {1908), 'So. .it,ii!. 

 pp. fi.')7, Ji58). — A full description is given of tlie wart or black-scab disease of 

 IK)tat(K'S, a previous account of which has been noted ( E. S. It., 10, p. 100). 

 The disease, wldch is due to the fungus Chrysophlyetis endobiotica, appears to 

 i)e spreading in parts of Europe. 



For its control, the autlior recommends the treatment of potatoes innnediately 

 after harvest with sul])liur, and, as the fungus is pro|tagated in the soil, where 

 a diseasiMl crop lias l)een grown rotation should l)e adopted. In the case of 

 the 4-course rotation, it should be so arrang«'d as to allow s years to intervene 

 before the next |)lanting of potatoes. Treatment of the ground with gas lime 

 early In the si)ring, after wldch it is top-worked, has proved efficient In holding 

 tiie dis(>ase in check. When potatoes are to be planted, it is recommended 

 that the cuttings be dusted with sulphur and sulphur siiread on the soil during 



