244 EXPEKIMENT STATION RECOED. 



All parts of a spectrum acted favorably on tlie germination of pine seed, the 

 long undulating rays being most beneficial and tlie short blue rays less beneficial. 

 Spruce seed was acted on favorably only by the red and yellow light and may 

 be directly injured by the blue light. 



In making seed tests it is sufiicient to germinate the seed under light condi- 

 tions for a period of from 8 to 10 hours daily. The best degree of light Is one 

 in which reading can be easily done. There was no important difference be- 

 tween the influence of daylight and of artificial light. Daylight tests should 

 preferably be conducted in rooms facing the north, where they will not be ex- 

 posed to the direct sunlight. 



Other conditions being equal the germination process of different seed sam- 

 ples may be traced in a curve, the latter course of which can be readily traced 

 by accurately recording the course of the curve during the first few days after 

 germination. For practical purposes a 12-day observation of tests conducted 

 at 25° is considered sufficient. 



Experimental rubber cultivation, J. B. Harrison (Rpt. Dept. Sci. and Agr. 

 Brit. Guiana, 1910-11, pp. S~13). — A progress reix)rt on cultural and tapping 

 experiments with indigenous and imported varieties of rubber yielding plants 

 during the year 1910-11 is presented. 



The rubber industry, edited by J. Torrey and A. S. Mandees (London 

 [1912], pp. JftO, figs. 51). — This is the official reix)rt of the proceedings of the 

 International Rubber Congress. Loudon, 1911. 



In addition to the matters relating to the organization and the functions of 

 the congress the following papers were presented : Rubber in Uganda, by R. 

 Fyffe (pp. 45-5S) ; The Production of Rubber in Madagascar, by the colonial 

 government of Madagascar (pp. 59-G8) ; Lecture on the West Indies, by F. A. 

 Stockdale (pp. 69-72) ; The West African Varieties of Latex and Raw Rubber, 

 by M. C. Hugot (pp. 73-80) ; Rubber Plantations in French Cochin China, by 

 A. Cremazy (pp, 81-86) ;- Rubber Trees and Wild Rubber Reserves of the 

 Amazon, by J. Huber (pp. 87-98) ; The Rubber Industry in Peru, by E. Castre 

 (pp. 99-104) ; The Rubber Problem in French Western Africa, by A. Chevalier 

 (pp. 105-119) ; Notes on the Planting and Production of Rubber in Ceylon, by 

 K. Bamber (pp. 120-131) ; The Need of Organization in the Supply of Literature 

 and Labor for Rubber and Other Planters, by H. II. Smith (pp. 135-141) ; 

 Official Measures against Adulteration of Wild Rubber, by G. van den Kerkhove 

 (pp. 142-148) ; The Maintenance of Health in Rubber Planting Districts, by 

 W. C. Brown (pp. 149-159) ; The Para (Hevea) India Rubber Tree in the East, 

 by H. A. Wickham (pp. 163-168) ; The Manuring of Rubber Trees, by E. Lierke 

 (pp. 169-179) ; Some Diseases of Hevea brasiUensis, by J. Mitchell (pp. 180- 

 189) ; Tapping Experiments on H. brasiliensis, by W. R. Tromp de Haas (pp. 

 190-196); African Rubber Vines: Their Cultivation and Working, by E. de 

 Wildeman (pp. 197-209) ; Notes on the Cultivation of Para Rubber, by W. Fox 

 (pp. 210-215) ; Some of the Constituents of PartJicnium argentatiim (Gray), 

 The Shrub from which Comes the So-Called " Guayule Rubber," by P. Alexander 

 (pp. 216-222) ; On the Physical Constitution of Caoutchouc-Bearing Latices and 

 the Relation of the So-Called " Coagulation " thereto, by H. C. T. Gardner (pp 

 225-230) ; The Centrifugalization of Rubber Latex, by H. S. Smith (pp. 231- 

 233) ; The DiscoveiT of the Para Reagent, by W. Pahl (pp. 234-242) ; Viscosity 

 of Hevea Latex at Various Dilutions, by Miss A. T. Borrowman (pp. 243-247) ; 

 Some Remarks on the Preservation of Rubber and on the Preparation of Plan- 

 tation Rubber, by AV. Esch (pp. 248-259) ; The Viscosity of Rubber and its 

 Solutions, by P. Schidrowitz and A. H. Goldsb rough (pp. 260-264) ; Raw Rubber 

 Testing, by C. Beadle and H. P. Stevens (pp. 265-284) ; India Rubber Research, 

 by F. Frank (pp. 301-305) ; Theory of Vulcanization, by W. Hinrichsen (pp. 



