1013 



placed, as well as the nearness of the houses to the grass-fields 

 favours the development of grasses; the vegetation thus becomes a 

 distinct grass-formation of a rather uniform type. The most frequent 

 grasses on the roofs in Thorshavn, for example, were Agrostis val- 



Fig. 195. Street in Thorshavn showing grass-vegetation on the roofs. 

 (Krom photo. by H. G. Simmons). 



garis and Festuca riibra. They occurred either as pure growths or 

 mixed together, occasionally with small patches of Holcus mollis, 

 Anthoxanthum and Poa pratensis. An almost complete absence of 

 »flowering« herbs is a pecuUarity not easily explained; only very 

 rarely did \ve see even a single flower on a roof. 



65* 



