475 



well covered with needles, lie on the ground. Preda^ describes a good 

 example from the Livornian coasts. Besides the slanting trunks, varieties 

 of pine and holly Juniperus phoenicea and Tamarix gallica are found bent 

 like snakes and the interwoven branches of Phillyrea and other bushes 

 creep over the ground. Hansen- gives a very similar description from the 

 Island of St. Honorat near Cannes. 



Bernhardt" characterizes certain regions in Germany as centres espe- 

 cially frequently visited by storms. As examples should be named Schwedt 

 a. O., the Silesian mountains, the Bavarian and upper Palatinate forests, the 

 forests of Franconia and, in a limited way, also the North German coast 

 (Mechlenburg, Holstein). In these coast lands, northeast storms in general 

 prevail as frequently as west and northwest storms, while in Southern Ger- 

 many, west and southwest winds have a decided preponderance ; in North- 

 ern Germany, as a whole, west and northwest winds. 



It is certain that the distribution of plants will adjust itself to the wind 

 conditions, since the varieties which withstand wind better have survived. 

 Schroter and Kirchner* quote, for example, Miiller's explanation of the dis- 

 tribution of the tree-like mountain pine {Pinus niontana) in the Alps. For- 

 merly this was found over a larger area, but because of its slow growth, 

 need of light and lesser demand had become limited to places where a differ- 

 ent forest vegetation cannot develop, viz., to wind-swept places with scanty 

 atmospheric humidity above the forest line. This wind resistance capacity 

 of the pine is probably connected with the anatomical structure of the 

 needles. Zang and Scheit consider the so-called transfusion tissue of the 

 vascular bundles a precautionary structure which, because of its constant 

 water content, makes possible the life of the needles in continuous dry air\ 

 Nevertheless, naturally, a definite limit may not be exceeded and Zang*^ cites 

 as an injury due to wind, the yellowing and drying of the tips of the needles. 



Certainly in conifer needles, the heavy waxy coating of the epidermis 

 and the schlerenchymatic sub-epidermal cell row, just as in the cacti, succu- 

 lent Euphorbiacae and Crassulaceae, increase the resistance to wind. 

 Gerhard" emphasizes, for the Cape flora, as a further protective arrange- 

 ment, the reduction of the intercellular spaces and the depression of the 

 stomata. He emphasizes the development of sclerotic hypoderm fibres and 

 the strengthening of the edges of the leaf by coUenchyma or bast bundles as 

 a mechanical effect due to the wind, which manifests itself in spite of the 

 moisture of the soil. 



1 Preda, L., Effeti del libeccio, etc. Bollet. Soc. Bot. ital. 1901; cit. Zeitschr. 

 f. Pflanzenkrankh. 1902, p. 160. 



2 Hansen, A. Flora oder Allgem. Bot. Zeitung- ]904, Vol. 93, Part I, p. 44. 



3 Die Waldbeschadigixngen durch Sturm und Schneebruch usw.; cit. Forsch. 

 auf dem Geb. d. Agrilvulturpliysik 1880, p. 527. 



■1 Kirschner, Loew und Scliroeter, Lebensgeschichte der Bliitenpflanzen Mittel- 

 europas. Vol.1, Part III, p. 207. 



5 See Scheit Die Tracheidensaume im Blattbiindel der Conifren. Jenaische 

 Zeitschr. f. Naturwiss. XVI. 1883. 



c Zang, W., Die Anatomie der Kiefernadel usw. Dissertation. Giessen 1904. 



' Gebhard, G., Beitrage zur Blattanatomie usw. Dissertation, Basel; cit. Bot. 

 Jahresber. 1902, II, p. 293. 



