921 



1. Nalural rormations and cultivaled (ornialions. 



2. Halophile and inland formations. 



3. Subalpine formations (in the lower regions) and alpine for- 

 mations of the mountains. 



In dealing with the natural inland formations the groups are 

 arranged according to their water-requirements, commencing with 

 Ihose which require most water. 



A. NATURAL FORMATIONS. 



,1. Bernatsky in a little paper (1904) has given an inleresting 

 summary of his views on plant-formations as influenced by man 

 and herbivorous animals. As it is of the greatest importance to 

 estimate precisely the great change in the vegetation of a landscape 

 brought about by man and animals, I have dealt with it in some 

 detail in the preceeding pages (pp. 892 — 895) and would again direct 

 attention to it. Classifying the plant-formations from this point of 

 view, Bernatsky gives three main divisions: 1) Natural forma- 

 tions, 2) Culture-formations, 3) Derelict formations, i. e. formations 

 on soils primarily cultivated, but afterwards abandoned to natural 

 vegetation. This last division does not appear to be so good as the 

 other two, because in my opinion the formations included under 

 this head might be distributed with no great effort under one or 

 other of the first two divisions. We shall adopt, therefore, only two 

 groups: natural and culture formations. Bernatsky 's analysis of 

 the natural formations inlo smaller divisions according to the de- 

 gree, in which they are influenced by animals and man, has much 

 to recommend it, but I think it will be more in accord with na- 

 tural conditions if I base my subdivision on other factors. We mav 

 how^ever utilize Bernatsky 's deflnition ofa natural formalion, viz: 

 »One in which all the elements have taken their piaces naturally, 

 and whose presence can in no way be altributed to human in- 

 fluence.« 



Several examples of Bern at sky 's groups occur in the pages 

 which tollow^ Thus the rock-vegetation, the Grimmia-heath, the 

 rocky-flat formation and others may be included in his »untouched 

 primeval formations«; while the grass-moor and the grass-slopes 

 are example of »formations, which have undergone a fundamental 

 change through grazing.« 



The first group of natural formations treated here includes 

 those influenced by the close proximity of the ocean. 



