DISEASES OF PLANTS. 241 



woods of different ages and density were carefully laid out and accurately 

 measured. 



Increase in the flow of latex from Manihot glaziovii as a result of peeling 

 off and scraping the outer layers of the bark, A. Zimmebmann (Pflanzer, 



10 (JDJJ/), No. Jf, pp. 180-188). — Data are given on tapping experiments con- 

 ducted by Fickenedy at the Kamerun experiment station and by the author 

 and Lomniel at the Amani station in German East Africa. 



The results of these experiments led to the conclusion that the flow of latex 

 can be increased by either peeling or scraping the outer bark. Scraping the 

 bark gives a much greater yield than that secured by peeling the bark off 

 entirely. It Is also less costly in practice and is less apt to injure the trees. 

 The employment of this method, especially on old and much tapped trees, 

 appears to be advisable. 



Report on an inspection tour of the rubber industry in Ceylon, the Straits 

 Settlements, and Deli, P. Arens {Medcd. Procfstat. Malancj, No. 8 (1914), 

 pp. 83, j)ls. 7). — This embraces the results of a survey of the rubber industry 

 in Ceylon, the Straits Settlements, and Deli, which was conducted with the 

 view of securing information of value for the development of the industry in 

 Java. The information secured deals with various planting operations, cul- 

 tural practices, tapping operations, preparation, grading, and packing of crude 

 rubber, etc. 



Creosoted piling in Galveston Bay bridge, F. B. Ridgway {Engin. Notes, 71 

 {191J,), No. 22, pp. 1176-1182, figs. i2).— Data secured from an examination of 

 bridge i)iling, the first lot of which was set in 1875 and removed in 1913, are 

 here reported. 



The results of the examination of these piles show that the 3S-year-old piles 

 which received a very light treatment of creosote are mostly destroyed. Over 

 00 i)er cent of about 3,000 IS-year-old piles which were given a heavy treat- 

 ment of creosote are still in good condition. 



A fence post test progress report, F. G. Krauss ( Hawaii. Forester and Agr., 



11 U91.'i), No. Jf, pp. 87, SS).— The results for the third season's test of euca- 

 lyptus fence posts (E. S. R., 20, p. 443) show the creosoted posts to be in the 

 best state of preservation, the tarred posts being the second best preserved. 

 The posts set in concrete are showing rapid disintegration. 



DISEASES OF PLANTS. 



The diseases of tropical plants, M. T. Cook {London, 1913, pp. XI-\-317, 

 pi. 1, figs. ,85). — This book, by the plant pathologist of the New Jersey College 

 Station, is primarily intended for the planter, but it will doubtless prove of 

 service to the student of tropical economic botany as well, as the author has 

 brought together a large amount of data scattered through many publications. 



After introductory chapters on the nature and symptoms of plant diseases, 

 the classification of fungi, and a description of other causes of plant diseases, 

 the diseases of many of the tropical economic plants are described at con- 

 siderable length, the arrangem.ent being according to the host plants. The sub- 

 jects of prevention and control and fungicides and spraying apparatus are 

 treated in separate chapters, although under many of the descriptions of dis- 

 eases specific recommendations are given for combating them. 



The author recognizes the limitations under which this work was prepared, 

 and he invites correspoodence and sugges'tions from plant pathologists of the 

 tropical world. 



Outline of administration in controlling insects and fungi injurious to 

 agricultural plants in Japan {Tokyo: Bur. Agr., Dept. Agr. and Com., 1913„ 



