NOTES ON RECENT RESEARCH. 



887 



NOTES ON RECENT RESEARCH. 



{See also imges 186 and 498.) 

 Alpine Plants. 



Alpine Plants, Dissemination of. By Paul Vogler {Flora, vol. Ixxxix. 



1901, pp. 1-137 ; 1 cut ; pi. i.-iv.). — This memoir deals with the methods 

 of dissemination of Alpine plants in the Alps from every point of view. 

 It contains (1) a systematic review of the characters of seed and fruit, 

 order by order, and species by species ; (2) a review of methods of trans- 

 port in the same order and with the same detail ; (3) a " general part," 

 with statistical tables, an analysis of the function of various transporting 

 agencies, reviewing the possibilities of each (such as the strength and 

 direction of the wind in various districts and at difierent times of the year), 

 the transporting powers af the wind as witnessed by the presence of 

 leaves, salt crystals, &c. Historical data as to immigration are obtained 

 from the visits of successive collectors. Thirty-five pages of tables and 

 seven of bibliography close the study. The author concludes that wind- 

 transport is far more active than animal- transport, and water-transport is 

 absent. This wind-transport, possible over distances up to hundreds of 

 kilometres, is only efficacious for distances of 3-40 kilometres. The pre- 

 ponderance of wind -disseminated plants is not due to their special direct 

 adaptation to Alpine conditions, but only to their being favoured in 

 immigration. The special significance of winged seeds and fruits is that 

 thereby the plants gain rapid possession of new stations, especially on 

 steep declivities. — M. H. 



The Ascent of Watek. 



Ascent of Water {Beih. hot. Cent. bd. xi. ht. 2, pp. 60-80).— Dr. 

 Kosaroff has studied the transpiration of leafless twigs during the winter. 

 He shows that they transpire water at the usual temperatures, and even 

 at 0° C. both in the laboratory and in the open air. Thus, during 

 winter, there must be a movement of water in the wood- vessels. The 

 amount taken in is not influenced greatly by small variations in the 

 external conditions. The amount of water absorbed is increased by high 

 and diminished by low temperatures, but this effect is not purely physical, 

 for it does not appear in the case of dried-up twigs. Light does not seem 

 to influence the absorption of water in the case of these leafless branches, 

 the amount of water taken in during the day and during the night being 

 about the same. Alcohol, ether, and carbolic acid have an injurious 

 effect ; weak solutions of corrosive sublimate have no effect, but strong 

 solutions increase the absorption of water. The living cells play an 

 important part in raising the water of li\'ing, though leafless, branches in 

 winter, as is shown by the difterence in the behaviour of dry twigs. The 

 paper contains the record of no less than thirty-four experiments (all in 

 tabular form), and must be considered as of extreme importance in all 

 (_[uestions dealing with the ascent of water in trees. — (/. F. S.-E. 



