CHAPTER XVI 



SUNSHINE, RAIN, AND WIND 



It is a fact that all flowering plants have somehow 

 suited themselves to some particular place in the world, 

 but it is very difficult to understand how they managed 

 to do this. The situations in which certain particular 

 species have established themselves are very strange. 

 One special alga lives only in the hollow hairs on the 

 toes of a rare South American sloth. 



The common darnel is generally affected by an inter- 

 esting fungus which develops in the seed. About 85 

 to 98 per cent, of the plants are so affected. When the 

 seed is sown and germinates, the fungus grows as the 

 seedling develops and again appears in the seed. It 

 does not injure the grass, which is even said to be more 

 vigorous when it contains the fungus. 1 



Dr. Borchardt found the seeds of this weed in certain 

 graves at Abusir in Egypt, belonging to the time of 

 King Newozee, that is, to 2400 B.C. So that this fungus 

 has continued to affect Lolium temulentum for at least 

 4300 years. 



In one particular cavern which is dark and moist 

 (the Hermannshohle at Riibeland), a special variety of 

 Bryum capillare is to be found which, so far as is known, 

 does not exist anywhere else. 2 There are lichens which 

 have trained themselves to living only on plaster or on 

 the resin of some particular kind of pine-tree. One 

 species has never been found except on burnt earth. 3 



Amongst flowering plants there are such forms 

 as Wulfenia carinthiaca, which is only known from one 

 particular rocky ledge (Gartnerskugel) in Carinthia. 



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