208 GLACIAL HISTORY. 



The largest colony of Alpine forms occurs in the upper Tossthal, 

 where 74 mountain-plants are found with 40 alpine species. 

 Prof. Heer has there seen Alpine roses (Rhododendron) and yel- 

 low auriculas,, gentian, and mountain buttercups, the odoriferous 

 Nigritella, and the Alpine forget-me-not ; nay, on the Schne- 

 belhorn, the Professor was surprised to find the Soldanella alpina, 

 the dwarf willow (Salioo retusa, Linn.), and the rock-speedwell, 

 which he had been accustomed to see only in the higher Alps. 

 The same phenomena are presented also at the Hohe-Rhonen, 

 which possesses 36 mountain-species, of which 18 are Alpine 

 plants. But even the low Albis range (which nowhere exceeds 

 2800 feet above the sea) and the Uetliberg comprise 7 Alpine 

 plants'*. And it is still more remarkable that even the Lagern 

 and the Irchel, notwithstanding their greater distance from the 

 high mountains, have yet received some Alpine colonists. 



In the low country the peat-bogs furnish plants which belong 

 particularly to the Alps or to high northern latitudes f; and, 

 what is still more remarkable, this is the case also in the peat- 

 bogs of Bavaria. 



As the Alpine vegetable colonies do not lie in the domain of 

 the rivers flowing from the Alps, these streams have not brought 

 down the plants into the lower portion of Switzerland. Nor 

 can their seeds have been conveyed by the wind ; for in two 

 thirds of the Alpine colonists comprised in the flora of Zurich 

 neither the fruits nor the seeds possess wings or any other 

 arrangements which might have fitted them for transport 



* On tlie Albis Prof. Heer has found the Alnus viridis, Linn. ; on the Uto, 

 Epilobium Fleischcri, Koch, Linaria alpina, Linn., Saxifraga aizoides, Linn., 

 Campanula pmilla, Pinguicula alpina) and Pinus montana, Mill.; on the 

 Lagern, Drdba azoides, Ardbis alpina, Ribes alpinum, Saxifraga aizoon, and 

 Adenostylis albifrons ; on the Irchel, Alnus viridis, Arctostaphylus Uva Ursi, 

 Aira montana, Veronica urticccfolia, Sambucus racemosa, Trifolium alpestre, 

 and Thesium alpinum ; and on the ridge between Rorbach and Bulach the 

 Alnus viridis. 



t Prof. Heer mentions as Alpine plants the chive (Allimn schcenoprasuni) , 

 the bogberry (Vaccinium uliginosutn) , the Alpine cotton-grass (Eriophorum 

 alpinuni), and the Sedum vittosum ; and as northern plants, Carex chordor- 

 rhiza and Scheuchze?'ia. Saxifraga oppositifolia, Linn., which grows in large 

 masses near Strad, not far from Constance, is also a plant of the Arctic flora 

 which has become acclimatized in the Swiss Alps. 



