1913] CURRENT LITERATURE 329 
that a progressive system of plant improvement cannot be a one-sided system, 
but must embrace all possible methods of reaching the desired end; (2) arti- 
ficial hybridization provides an invaluable means of obtaining characters in 
superior combinations which do not occur in nature and this method is now 
largely used at Svaléf for this purpose; (3) the old system of “mass selection” 
can still be of value in special cases and has never been fully abandoned; 
such characters, the valuation of these individuals (or lines) to rest upon tests 
conducted with the greatest care and extending over a series of years. This 
means the recognition of the importance of physiological as well as morpho- 
logical unit characters, and the abandonment of reliance upon the use of 
correlation of characters as any important aid in estimating the practical 
value of an individual or line. 
Detailed reports of some investigations, some sixty illustrations from 
practically all accounts hitherto written in a foreign language.””—Gro. D 
ULLER. 
The cotton plant 
W. Lawrence BALLs, “cryptogamic botanist” on the staff of the Khedi- 
vial Agricultural Society, has published a volume on the cotton plant in Egypt.‘ 
It brings together information of the most varied character, the material being 
assembled as if to “take account of stock” preliminary to a fuller monograph. 
The four sections of the book treat of the history of cotton in Egypt, the 
individual plant, the race, and the economics of cotton, the second and third 
sections being of special interest to botani 
In the account of “the individual ae, a brief outline of fertilization 
(including the conspicuous cytological features) and embryology is given 
(8 pp.), followed by an account of experimental work on “development and 
environment” (67 pp.). This physiological work includes such topics as 
germination conditions, temperature and growth, effect of sunshine, night 
temperatures, hypocotyl and root growth, transpiration (including its relation 
flowering curve, etc. The cotton fiber of course is described in detail (8 pp.). 
In the account of “the race,” the problems of fluctuation, commercial varieties, 
natural crossing, and heredity are presented (87 pp.), quite a number of graphs 
presenting to the eye the results of much experimental work.—J. M. C. 
* Batts, W. Lawrence, The cotton plant in Egypt; _ in physiology and 
genetics, np: xvi+202. figs. 7z. London: Macmillan & Co. rgiz. 55 
