F. KiDD AND C. West 249 



factors which have operated previously to, or during, germination. It is 

 obvious that the environmental conditions which obtain during ger- 

 mination affect the vigour of the seedling, and in the present review of 

 literature attention has been directed to special seed-treatments which 

 have been found to stimulate not only germination but also the growth 

 of the plants produced. The critical question is therefore — Can we 

 propound a law to the effect that increased vigour of seedling develop- 

 ment due to environmental conditions as distinct from hereditary causes, 

 is correlated with increased vigour of growth throughout the life of the 

 plant and with increased yield independently of the subsequent environ- 

 mental conditions? 



Experimental work should be concentrated on this distinction. If 

 the principle of physiological, as distinct from hereditary, pre-determina- 

 tion was fully established, many of the methods of seed-treatment 

 which have been found to stimulate germination and the growth of the 

 seedling could probably be developed, and employed in the field and 

 greenhouse as a means of increasing production. 



(To be continued.) 

 Literature Cited. 



(1) Andee, G. Deplacement par I'Eau des Substances Nutritives contenues dans 



les Graines. C.B. de VAcad. des Sc. Paris, 154, 1912, p. 110. 



(2) Babcock, S. M. Metabolic Water: Its Production and Role in Vital Phenomena. 



Univ. of Wisconsin Agric. Expt. Sta., Research Bull. 22, 1912. 



(3) Bbown, H. T. and Morris, G. H. Researches on the Germination of some of 



the Gramineae. Journ. Chein. Sac. (Land.), Trans. 57, 1890, p. 458. 



(4) Btjckner, G. D. and Kastle, J. H. The Growth of Isolated Plant Embryos. 



Journ. Biol. Chem. xxix, 1917, p. 209. 



(5) CoupiN, H. Sur la Resistance des Graines a I'lmmersion dans I'Eau. C.B. de 



VAcad. des Sc. Paris, 126, 1898, p. 1365. 



(6) Davis, W. E. and Rose, R. C. The Effect of External Conditions upon the 



After-ripening of the Seeds of Crataegus mollis. Bot. Gaz. Liv, 1912, p. 49. 



(7) Delassus, E. Influence de la Suppression Partielle des Reserves de la Graine 



sur le Developpement de la Plante. C.B. de VAcad. des Sc. Paris, 153, 

 1911, p. 1494. 



(8) Influence de la Suppression Partielle des Reserves de la Graine sur 



I'Anatomie des Plantes. C.B. de VAcad. des Sc. Paris, 157, 1913, p. 228. 



(9) DuBARD, M. et Urbain, J. A. De I'lnfluence de I'Albumen sur le Developpe- 



ment de I'Embryon. C.B. de VAcad. des Sc. Paris, 156, 1913, p. 1086. 



(10) Sur quelques Cas Teratologiques de Germination chez le Chou-fieur et 



le Chou-Milan. Rev. gen. de Bot. 25 bis, 1914, p. 203. 



