235 



spleniiwi are h o m o ^' a m o u s or oscillate around homogamy ; it 

 is especially the small- fl o\ye red species, which are homo- 

 gamous. 



Protogyny occurs in S. cernua, groenlandica, hieracii- 

 foUa, nivalis^ and stellaris, but usually slightly Most distinctly 

 and decidedly protogynous is »S. oppositi folia. 



I may add that Asa Gray ("Notes on some North American 

 Species of Saxifraga," in Proceedings of the American Academy, 

 XX) states that most of the individuals of S.peltata have pro- 

 tandrous flowers ; but that it is not rare to find some which 

 are truly protogynous, and that the species shows a decided 

 tendency to become gynomonoecious. In the Hortus hafniensis 

 S. peltata is seen to be protogynous. Regarding S. granulata, 

 Gaston Bonnier says : "On peut voir chez ce Saxifraga des 

 fleurs presque mâles, des fleurs presque femelles, et en outre 

 tous les intermédiares." (Bulletin de la Soc. botan. de France, 

 VI, 1884, p. 240). 



The staminal movements are those usual in the Saxi- 

 fraga (see, e. g. p. 174). 



Self-pollination is evidently very common. The small- 

 flowered species are all more or less distinctly self-pollinating. 

 Among the larger-flowered, several are evidently distinctly self- 

 pollinating, if not in the first stage of the flower, then some- 

 what later. In the Botanic Garden of the University of Copen- 

 hagen S. groenlandica is more distinctly protandrous than in 

 Greenland; it is true that, in the latter place it is also deci- 

 dedly protandrous, but there the flower soon becomes homo- 

 gamous and self-pollinating. The possibility of self-pollination 

 will mo.st probably always ultimately occur by the flower becoming 

 homogamous, and stigma and anthers approaching and possibly 

 touching each other, t.g.'m S. Aizoon, cernua,flageUaris, groen- 

 landica, hieraciifolia, nivalis, oppositifolia and Chrysospleniuni. 



VI. Fruit-setting and seed-formation is common in 

 many species everywhere in the Arctic countries, and rare or 



