22 2 THE PLANT WORLD. 



REVIEWS, 



The Physiology of Plants. A Treatise upon the Metabolism and 

 Sources of Energy in Plants. \^olume III. By Dr. W. 

 Pfeffer. Second fully revised edition. Translated by Al- 

 fred J. EwART. Large 8vo. Pp. 451, with many illustrations. 

 Oxford: The Clarendon Press, 1906. 21 shillings. 



Every student of botany knows so well the character and 

 usefulness of Pfeffer's magnum opus that criticism would be 

 quite beside the mark. The translation has been long expected, 

 and is at last welcomed. To the translator belongs no small 

 amount of praise and congratulation — praise for the excellence 

 of the labor, and congratulation on its completion. But for the 

 universal acknowledgment accorded the author and his work, so 

 brief a notice would ill fit the great value of the book. 



Mosses zvith Hand-lens and Microscope. A non-technical 

 Handbook of the more common Mosses of the Northeastern 

 United States. By A. J. Grout. Part III. Quarto. Pp. 

 167-246. Richly illustrated. Published by the author, 360 

 Lenox Road, Brooklyn, New York. 1906. $1.25. 



It will bear repeating that the author of Mosses with the 

 Hand-lens and Microscope deserves the thanks of students of 

 the mosses of this country for the work of which the third part 

 is now to hand. It contains, besides many other very clear and 

 useful illustrations, about twenty full page plates reproduced 

 from the Bryologia Europcea and Sullivant's I cones, thus, to 

 this useful extent bringing original literature to the use of the 

 person interested in these plants, but who is removed from the 

 privileges of the large library. Dr. Grout's treatment is gener- 

 ally stimulating, and the book will certainly further greatly the 

 wide study of the mosses. The earnest elementary student will 

 get from it a very great deal of the help that he needs. The 

 typography is excellent. 



