218 



Remarks un the most Important Plant-Societies of the Island. 



Fig. 73. Epipactis veratrifoUa Boiss, et Holieuack. ('/a)- 



To the left of the flowering stem is seen the rest of that of the preceeding year: 



to the right a creeping stolone. 



It grows partly on the vei-y banks 

 of the rivers, partly on the many 

 big-grer or smaller gravel banks and 

 islands in the riverbeds, the bottom 

 of which are very flat. Now and 

 then may be found— between thou- 

 sands and thousands of bushes with 

 red flowers— some single copies 

 with white flowers. 



As is the case with many 

 other genuine marshy plants, especi- 

 ally shrubby plants, thus also Nerium 

 Oleander, as is well known, has a 

 decidedly xerophilous structure of 

 its leaves; the leaves are thick, 

 coriaceous and are distinguished 

 by the stomata being hidden inside 

 smal cavities, the openings of which 

 are almost entirely secluded through 

 some peculiar hair-foi'mations. Mi- 

 nute particulars of the structure 

 of the leaves of Nerium will be 

 found in the common text-books 

 on plant-anatomy, e. g. in Stras- 

 BURCfER's „Botan. Practicum".') — 

 It is a very striking fact that 

 a lot of plants growing in wet pla- 

 ces through the structure of their 

 leaves should be thus as strongly 

 defended against evaporation as the 

 most typical xerophytes. Warming 

 treats of this fact in his book 

 „Plantesamfund" in a special chap- 

 ter (p. 147—150). lu addition to 

 the moments given there to explain 

 this circumstance, there is, how- 

 ever, anothei- moment which I think 

 is of great importance, at any rate 

 as far as Nerium is concerned and 

 also regarding the chief part of 

 the plants found in peaty soil men- 

 tioned by Warming. The soil in 

 which these plants are growing is 

 indeed so watery as a rule that 

 they generally have full access to 

 all the water they need. At the 

 same time, however, it ought to be 

 remembered, that the typical habi- 

 tations of these plants are absolutely 

 open to the sun, and that their 

 leaves are constantly exposed 

 to its rays. Everybody who has 

 passed through the Eastern paits 



') E. .Sthasbi'hgkr, Das botanisclie \'ra.v-th 



Dritte Auflage. p. 170. .lena 1897 



