September, 1911.] 



268 



Reviews, 



Mr. Peteh shows incidentally that the 

 earlier Henaratgoda experiments were 

 unreliable, probably owing to insufficient 

 supervision, indeed the reliable data in 

 all matters of tapping are so extremely 

 meagre that we cannot help thinking 

 the analysis to which Mr. Petch has 

 subjected it somewhat excessive. 



With regard to the structure of the 

 laticiferous system (p. 17) this should 

 rather be stated to consist of a series of 

 concentric networks. So far as we are 

 aware the presence of radial connections 

 between the different layers of latex 

 tubes has not been demonstrated. 



The statement that the use of latex to 

 the plant does not lie in the protection 

 which it affords against the attacks of 

 insects appears to be a little dogmatic. 

 Adherents of the theory of adaptation 

 have put forward much more surprising 

 views than this, and their views have 

 been received with almost universal 

 respect. 



It is scarcely necessary to recommend 

 the chapters dealing with the actual 

 fungus disease to anyone who is 

 acquainted with Mr. Petch's circulars 

 upon this subject. The two familiar root 

 diseases — Pomes and Hymenochsete— 

 are described together with one which 

 is less common, Sphserostilbe. The three 

 commonest diseases of the stem are well 

 known by the popular names of canker, 

 which has been shown to be identical 

 with the stem and pod disease of cacao, 

 pink disease, for which an earlier 

 scientific name — Oorticium salmonicolor- 

 is shown to take precedence of the more 

 familiar (7. javanicum and die- back. 

 Three other stem diseases are also 

 recorded, one for the first time. In 

 addition to these there appear to exist 

 three leaf diseases. 



Perhaps the most important chapter 

 of all from the planter's point of view 

 is the one dealing with general sanita- 

 tion. The following extract affords 

 material for thought :— " All the root 

 diseases of Hevea, tea, and cacao, which 

 have been investigated with any 



approach to completeness have been 

 found to originate on a neighbouring 

 stump ; in some cases it is the stump of 

 a jungle tree, while in others it is the 

 stump of a tree which has been planted 

 for shade and then cut down. But there 

 is no known root disease of any of the 

 plants mentioned which attacks the 

 plant directly, i.e., by the germination 

 of spores upon the plant ; they all 

 require au external base of operations, 

 and this they find in the dead wood of 

 an adjacent stump." 



Amongst abnormalities Mr. Petch 

 still attributes the greatest number of 

 cases of the formation of woody nodules 

 to the use of the pricker, an instrument 

 which he does not hesitate to condemn 

 in all its forms. No discussion is how- 

 ever given of those apparently some- 

 what frequent eases where pricking or 

 other forms of tapping ou one side of 

 the tree seem to lead to the formation 

 of nodules on the opposite side. 



In conclusion, we may tender to Mr. 

 Petch our congratulations on producing 

 a very interesting book, and one which 

 should be read by all who are interest- 

 ed in the plantation rubber industry. 



R. H. LOOK. 



THE CULTIVATION OP HEVEA. 



By P. J. S. Cramer, 

 Director of Agriculture in Surinam. 



Translated by S. R. Cope and A. Content. 

 Amsterdam, 1911. 

 This is a small but well-illustrated 

 book, based on a journey in Ceylon and 

 the F.M.S. in 1910, and is well worth 

 perusal. It gives a clear and succinct 

 account of the various operations involv- 

 ed in rubber cultivation, such as Clear- 

 ing, Drainage, Nurseries, Planting, Up- 

 keep, Catchcrops, Diseases, Tapping, 

 and Curing. The accounts of all these 

 are very well and clearly put, and what 

 to do, and what not to do, is brought 

 out- The book may be cordially recom- 

 mended to the young planter. 



