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THORODDSEN 



coppices, as independent formations, have but a slight distribution 

 in Iceland. As stated above, Salix lanata and S. glanca are distri- 

 buted over extensive sandy areas, and occur there, together with 

 some other plants, as dominants; in other places they occur on dry, 

 flat, clayey tracts, as scattered shrubs of low growth (20 60 cm.) 

 with an undergrowth of heather, Elyna Bellardi, various species of 

 grasses, etc. It is chiefly Salix phylicifolia which forms coppices 



Fjg. 35. Knolly moor of Betula liana intermixed with Salix lanata and SalLv phylicifolia 

 Ground vegetation: Empetrnm. Arctostaphylus iwa ursi, Anthoxanthum odoratum and 



Polygonum uiviparum. (Phot. A. Hesselbo.) 



(e. g. near Skaftafell, Fnjoskadalur, Hrafnkelsdalur, Kaldalon and 

 Myvatn) in association with Salix lanata and Betula odorata and 

 with a rich ground-vegetation of highly diverse plants common on 

 "herb-flats." Now and then Salix phylicifolia forms the undergrowth 

 of birch coppices, as for instance, in Bsejarstadaskogur near 0rsefi; 

 the willows here have an average height of 2 metres; the highest 

 individuals are 3 metres in height, but the stems are only 18 24cm. 

 in circumference. Salix phylicifolia (often together with Salix lanata, 

 which may attain a height of I--! 1 /? metres) is often found inter- 

 spersed in birch coppices, in many places in different districts. In 

 Several places near Myvatn Salix phylicifolia forms coppices, among 

 other places in Sluttnes, where a stem which I measured in 1882, 



