50 



MADRONO 



[Vol. 1, 



At the marshy margin of alpine lakes and ponds thrives, espe- 

 cially on siliceous ground, a grasslike plant of arctic origin, the 

 cotton-grass of Scheuchzer (Eriphorum ScheucJizeri Hoppe). You 

 see it here fringing with snowy fruiting heads the shallow water of 

 little depressions between the roches moutonnees near Bernina hos- 

 pice. The white color is also here the effect of the air-filled hairs; 

 they accompany the fruit and serve as a flying apparatus, helping 

 the distribution by the wind. They have nothing to do with trans- 

 piration nor advertisement, the air is here exclusively as a means 

 for diminishing the weight. 



We have now made the acquaintance of some of the principal 

 types of meadows and pastures. We leave them to study the flora of 

 rubbles and rocks. 



The moving slopes of rubbles, the screes, have quite peculiar 

 conditions of life for their inhabitants. The stones menace continu- 

 ally their shoots and the soil is distributed in little heaps on sepa- 

 rate stones ; therefore we find special adaptation in the scree-plant. 



The round - leaved 

 Penny Cress ( Tli laspi 

 rotundi folium (L.) 

 Gaudin) (Fig. 24) is 

 one of the most constant 

 inhabitants of moving 

 debris; never do we find 

 it on the pasture. The 

 special method of avoid- 

 ing the dangers of its 

 habitat consists in 

 spreading with long flex- 

 ible creepers through 

 the gaps between the 

 loose stones, here and 

 there sending out root- 

 lets where it finds a lit- 

 tle sediment of detritus. 

 With isolated aerial 

 shoots it emerges from 

 the rubbles to unfold its 

 roundish leaves and its 

 violet flowers. The plant 

 is an endemic product 

 of our Alps. In similar 

 manner the bluebell of 

 Mt. Cenis (Campanula 

 cenisia L.) penetrates 

 with long shoots the 

 narrow gaps in the rub- 

 ble slopes. 



Fig. 25. White Alpine Poppy (Papaver al- 

 piiium L. var. Sendtneri Kerner), in lime- 

 stone screes at the Pilatus near Luzern, 1,900 

 meters above the sea. Photo Guyer. 



