BOOKS AND CURRENT LITERATURE 



Cotton in Egypt. — The author of this work/ the fifth of a series of 

 Science Monographs pubHshed by the IMacmillan Company, has been 

 for some years, since 1904 indeed, officially concerned, as an attache of 

 the Egyptian Department of Agriculture, with a study of the cotton 

 plant. That a definitely recognizable deterioration of the lint of the 

 much desired long staple cotton has taken place during the more recent 

 period of its cultivation in Egypt, is well known to spinners and stu- 

 dents of the plant. This is one of those perplexing problems, in agri- 

 culture if one will say so, which can be understood and corrected only 

 by the application of accurate method. This was, primarily, the task 

 undertaken by Mr. Balls, who has approached the matter from the 

 physiological and from the genetical points of view. Of particular inter- 

 est to the plant physiologist is the author's attempt, hy no means unsuc- 

 cessful, to sublimate field ecological methods, thereby bringing them 

 into the domain of stricter physiological experimentation. To have 

 recorded stomatal action automaticallj- in field plants for a sustained 

 period by means of an ingenious device, the stomatograph, an auto- 

 graphic elaboration by Air. Balls of Dr. Francis Darwin's porometer, is 

 a distinct achievement and this instrument and its work must turn out 

 to be of very great value to the plant physiologist and ecologist; this 

 quite aside of the question of the precise meaning to be attached at the 

 moment to the rate of draft of air through the leaf. The inference that 

 such air movements are a function solelj^ of the condition of the stomatal 

 openings is, in the opinion of the reviewer, .susceptible of criticism, for 

 one can very readily conceive of increased internal friction lowering the 

 rate of air movement independently of change in the dimensions of the 

 stomatal aperture. At any rate, an opportunity is now afforded, by 

 combining Mr. Balls' method with one devised by the reviewer^ whereby 

 it may be possible to differentiate between the stomatal movement and 

 change in the mechanical condition of the interior of the leaf. 



1 Balls, W. Lawrence, The Cotton Plant in Egypt. Svo, pp. xvi + 202. Lon- 

 don: The MacmLUan Company. 1912. ($1.60.) 



- Lloyd, Francis E., Leaf water and stomatal movement in Gossypiutn. Bull. 

 Torr. Bot. Club 40: 1-26. January 1913. 



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