357 



before the flower expands the outermost stamens elongate and 

 they open before the glistening papillae can be observed upon 

 the stigmas. The homogamous stage is the longer. Spon- 

 taneous self-pollination may take place at night when the 

 flowers are closed (cf. Lindman, p. 30). In Nova Zembla Ekstam 

 found prologynous-homogamous , homogamous, and protan- 

 drous-homogamous flowers. In Denmark I have found besides 

 the common hermaphrodite flowers, others with carpels not 

 fully developed; Fig. l^ B^, B.,, shows two carpels, both from 

 flowers of which the stamens had shed almost all their pollen; 

 B^ is fertile, B.^, together with the other carpels in the same 

 flower, is without papillae. When the flowering is over, plants 

 are commonly found bearing, only barren, shrivelled-up 

 carpels. 



The pollen is protected from rain by the peduncle 

 bending, during wet weather, so that the flower-cup is turned 

 downwards. 



The flowering begins in May-June, somewhat earlier in 

 Denmark than in the Arctic regions, and may be continued 

 into September. (Norman, Rosenvinge, 11). 



The fruit, like the fruits of the majority of the species of 

 Ranunculus, does not appear to be especially adapted to any 

 particular dispersal-agency. Examples of wind-dispersal are 

 however known (EkstamI, and it may be presumed that some 

 are dispersed by the agency of water. Of 200 fruits, which 

 lay in quiet water, the last sunk after 3 days, while of 100 

 fruits, which lay in water which was frequently stirred, all 

 sank before the expiration of 24 hours. Norman believes that 

 synzoic dispersal by means of cattle takes place, and mentions 

 having found germinating plants in cow-dung. 1 fed a heifer, 

 in May, 1910, with fruits of the previous year, and 36 hours 

 after, 80 apparently unhurt specimens of these were washed 

 out of the dung; they were immediately sown and seven (8-8 ^/o) 

 germinated. 



