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CURRENT LITERATURE 



BOOK REVIEWS 



Two ecological monographs 



Climatic adaptations. — Supported by a grant from the Royal Prussian Acad- 

 emy of Sciences in Berlin, Dr. Carl Holtermann was able to spend some time 

 at the botanical gardens in Peradeniya and Buitenzorg, where he carried on in- 

 vestigations upon the anatomy and physiology of tropical plants, returning to 

 Berlin with a very rich collection of alcoholic material, only part of which has 

 yet been investigated. The first fruits of these investigations form a bulky volume 

 (which might easily have been made less imposing and more convenient) upon 

 the influence of climate on the structure of plants.^ 



The work is dedicated to Schwendener (in honor of the fiftieth anniversary 



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of his doctorate), and the author naturally looks upon plants from the same 

 view-point as the Meister — "dass im inneren Bau der Pflanzen eine weitgehende 

 Zweckmassigkeit herrscht, dass Bau und Funktion bis in die kleinsten Einzel- 

 heiten in Harmonie stehen." 



In the first section, on the transpiration of tropical plants, Holtermann 

 shows that both Haberxandt and Giltay are right in certain points. The 



maxmaum 



m 



all there are certain periods, lasting from four or five hours to one or two days, 

 in which transpiration is so extremely vigorous that the plants suffer for lack of 

 water. As compared with European countries, the total transpiration in 24 hours 

 is less; in the middle of the day, however, it is often decidedly greater in the 

 moist tropics, values being obtained which are not reached even in the hottest 

 days in Berlin; yet these maxima usually last only a few hours. In rainy weather, 

 for days together transpiration ceases entirely. This, as Holtermann points 

 out, is not surprising to pupils of Schwendexer, who for more than a generation 

 has treated transpiration in his lectures as a necessary physical process, which 

 indeed induces physiological consequences, but is no indispensable function. 

 The wonderful vegetation of those regions where the rains for months at a time 

 are continuous, or are at most only replaced by a dense fog, speaks strongly against 

 the prevalent view of evaporation as a function; and so do Holtermann' s experi- 

 ments with Impatiens, which grows well in saturated air. 



The second section, on tropical vegetation zones, is devoted to showing how 

 the members of the various plant societies show like anatomical adaptations to 



Klimas 



Anatomisch-physiologische 



fiS^' 7- P^^' ^^- Leipzig: Wilhelm Engelmann. 1907. M 



228 



Imp. 8vo. pp, viii + 247 



