FOEESTRY. 843 



of the rubber-yielding trees of ttie genera Periploca, Cryptostegia, Clitaudra, 

 Landolphia, Ifuntumia, Hevea, Manibot, Ficus, and Castilla, which are believed 

 to be of especial importance for the Belgium colonies. The structure of the 

 different species is described and also illustrated in a series of plates. 



Scientific studies of Hevea brasiliensis, A. W. K. de Jong {Dept. Lanclh., 

 Nijv. en Handel [Dutch East Indies], Meded. Agr. Chem. Lah., WIS, No. Jf, pp. 

 37. taMes 10, pi. 1, figs. 12). — The author here reports tapping experiments with 

 Hevea rubber trees in which special attention was pjiid to the method of 

 tapping and direction of cut in relation to the latex system of the tree. The 

 results of these investigations are discussed at length. A fertilizer test was 

 also conducted with a number of trees in which the complete fertilizer gave the 

 best results. 



Hevea: Yields of some Henaratg'oda trees, R. N. Lyne (Dept. Agr. Ceylon 

 Bui. 4, 1913, pp. 61-73, figs. 2). — This bulletin contains the results of tapping 

 investigations conducted on 3 old Hevea plantations at Henaratgoda. The 

 tests were conducted with reference to both girth measurement and the effect 

 of straid density on the yield. 



The results thus far indicate that after a certain size has been reached 

 increased girth measurement does not necessarily mean increased yield. They 

 also suggest the importance of allowing the trees ample room for root and crown 

 development. 



Tapping Ceara (Manihot glaziovii), P. Abens {Meded. Proefstat. Malang, 

 1913, No. 6, pp. 32). — Tests of various methods of tapping Ceara rubber con- 

 ducted at the Malang Experiment Station are described and suggestions are 

 given relative to the practical application of the results. 



The half-herringbone method as employed in tapping Hevea trees proved to 

 be the best system for Ceara trees, but the vertical channel was found to be 

 unnecessary. Four cuts on the half-herringbone system, 30 cm. between cuts, 

 yieldetl practically twice as much as 2 cuts 30 cm. apart, but 8 cuts spaced at 

 15 cm. apart gave less than 3 times as much as the 2 cuts 30 cm. apart. Of 

 cuts made on 10 trees at 40 cm., 120 cm., and 2 meters, respectively, from 

 the ground the yield in about 6 weeks' tapping was 143.73 gm. for the lowest 

 cuts, 106.42 gm. from the intermediate, and 103.67 gm. from the highest cuts. 

 On another group of 10 trees cuts 30 cm. long and cuts only 15 cm. long were 

 made on the same trees. On 5 trees the long cuts were made below a height of 

 50 cm. and the short cuts above 1 meter. On the other 5 trees the positions were 

 reversed. In 6 weeks' daily tapping the long cuts yielded 174.23 gm. and the 

 short cuts 111.44 gm. 



Three years is believed to be sufficient time to allow for bark renewal on 

 Ceara trees since it takes place much more rapidly than on Hevea trees. 

 The results of the tests as a whole indicate that the culture of Ceara rubber 

 should be confined to locations where Hevea rubber can not be grown success- 

 fully. 



Wood-using' industries of Ontario, R. G. Lewis and W. G. H. Boyce (Dept. 

 Int. Canada, Forestry Branch Bui. 36, 1913, pp. 127). — This comprises an account 

 of the quantity, value, and source of supply of the different kinds of wood 

 used by the various industries of Ontario. It includes detailed descriptions of 

 the different classes of industries and of the properties of the woods used 

 therein. 



Forest products of Canada, 1912. — Poles and cross-ties, R. G. Lewis and 

 W. G. H. BoYCE {Dept. Int. Canada, Forestry Branch Bui. 39, 1913, pp. 16). — A 

 statistical report of the quantity, value, and kinds of poles and cross-ties used 

 in Canada in 1912 with comparative data for 1911. 



