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SKETCHES OF VEGETATION AT HOME AND ABROAD. 
V.—The Ecology of the Upper Driva Valley in 
THE DOVREFJELD. 
By W. West, F.L.S., and G. S. West, M.A., D.Sc., F.L.S. 
[Plates III and IV and Text-Figs. 26—32]. 
I N 1909 we spent the month of August in the upper part of the 
Driva Valley, making our head quarters at the Kongsvold 
posting-station, which lies towards the northern limit of the 
Dovrefjeld. Every day, in sunshine, rain, or snow, we were inves¬ 
tigating the valley or the surrounding mountains, with the result 
that we accumulated much botanical material and information. 
The district was reached via Christiania and Lille-Elvedal, 
leaving the train at the last-named place (alt. 1660 feet) and driving 
for the next 61 miles along the only road which traverses this part 
of Norway. The difficulties of the road, combined with the 
