167 



The further one proceeds northwards in the Arctic regions, 

 he more imperfect is the development of the fruit, as might 

 be expected; Warming (20, p. 52) cites Vahl, according to 

 whom the fruit of Empetrum sometimes does not ripen in the 

 district of Upernivili. Also other notes on the rudimentary 

 development of the fruits are to be found in the literature 

 dealing with the subject. In connection with this may be 

 mentioned the very important information given by Andersson 

 and Hesselman (2, p. 31) when they write that the fruit of 

 Empetrum was never observed in Spitzbergen and that, pre- 

 sumably, it is sterile (?) there. Haglund (6, p. 31) says that on 

 the stony flats at Vassijaure the fruit often does not ripen. 

 Now, the variety (var. purpureum (Rafin.) DC.) described by 

 Rafinesqde, is it not just such a form, with imperfectly developed 

 fruit? In addition to which it has been found only in Labrador, 

 New Foundland, and inN. W.Greenland (see Simmons 15, pp.42— 43). 



The fruit of Empetrum often persists through the winter 

 and sometimes preserves an entire skin, and is juicy, etc.; it 

 belongs to the "vinlerståndare."^ There is no doubt that the 

 fruits are largely dispersed by the help of animals; both mammals 

 (foxes, lemmings, and doubtless bears) and birds eat them in 

 great quantities. Selim Berger (Svensk botanisk Tidskrift, 1907) 

 mentions that ptarmigans and black grouse especially play a 

 prominent part in transporting the seeds of Empetrum. The 

 old and, in itself, reasonable conjecture of Buchenau that the 

 seeds, in order to be able to germinate properly, must pass 

 through an alimentary canal (B. says that of a bird), has not 

 yet been verified by experiment. 



1 Sernander's term for plants, upon which the fruits remain throughout 

 the winter (Den skandinav, vegetationens spridningsbiologi, p. 353). 



./«^ 



20. — 2.— 1909. 



