CURRENT LITERATURE 
BOOK REVIEWS 
Ecological plant geography 
The name of WARMING always comes first to mind when one thinks of the 
great names in modern ecology. In November 1g21 he passed his eightieth 
milestone, receiving a portrait album together with the congratulations of his 
coworkers in all lands. Ten years ago he retired from active service at the 
University of Copenhagen, but these ten years have been full of important 
researches, and his publications during this period have been numerous. One 
of the most important of these publications is the third German edition of his 
he firs 
being essentially an unmodified translation by KNnostaucs of the original 
without cooperation with WARMING. The English edition of 1909 was essenti- 
ally a new book, with a very different grouping of the subject matter, in which 
WarMING, although it follows the general features of the English edition. “The 
most conspicuous changes are seen in the chapter that deals with formations 
and associations, and here the author follows the recommendations of the 
Brussels Congress of 1910. The book is also much larger than preceding 
editions, and the references to the literature are brought to date, so far as 
possible. But for the war, the book would have appeared much sooner than 
it did. It was asked for by the publishers in 1912, and was ready in 1914.— 
H. C. Cow es. 
Principes de Biologie aes 
Following his volume on L’Evolution des Plantes, published in 1918, the 
second posthumous volume of BERNARD’s? lecture notes has been published 
under the title Principes de Biologie vegetale. The first part deals with cellular 
physiology of plants, with chapters on the principle of determinism, physical 
conditions of nutrition, nutritive metabolism, carbon nutrition, nitrogen nutri- 
tion, and the action of exterior agents upon the living cell. The second part of 
*Warminc, Evc., and GraEBNER, P., Evc. Warmino’s Lehrbuch der dko- 
logischen Sis cnc daahier dritte umgearbeitete Aufiage. pp. 762. Berlin: 
Gebriider Borntraeger. 1918. 
2 BERNARD, NOEL, Principes de Biologie vegetale. pp. xiit+212. figs. 18. Paris: 
Felix Alcan Library. 1921. 
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