Rosaceæ. 71 



they appear to agree as regards the structure and the biology 

 of the flower. Warming (1. с 1886 a, pp. 127— 28) has 

 described and figured the flower of D. integrifolia. He writes: 

 "that as D. octopetala (in Norway, Spitzbergen and the 

 Alps) this also has hermaphrodite and male flowers and from 

 a biological point of view they appear on the whole to resemble 

 each other exactly." — Fig. 28 is a reproduction of his figure; 

 A shows a branch with the terminal flower; B, a herma- 

 phrodite flower; C, a male flower, at the base of the hypan- 

 thium of the latter are seen some pistil-rudiments. — "As in 

 D. octopetala the hermaphrodite flowers are larger than the 

 male flowers, but the smallest forms of the former are some- 

 what smaller than the largest of the latter" ^. — According to 

 Simmons (1. c.) the flower of D. integrifolia is on an average 

 somewhat smaller than the average size of the flower of D. 

 octopetala. — "The petals (8 — 11) are white or yellowish-white 

 while young, but with increasing age become darker yellow or 

 brownish yellow." — In D. octopetala they are almost pure white 

 (Simmons). — "It appears that the hermaphrodite flowers may 

 be both homogamous and slightly proterogynous or slightly 

 proterandrous; on July 15, 1884, I gathered near Amerdlok- 

 fjord (W. Greenland) flowers, the anthers of which were open 

 while the styles were still short, and the stigmas appeared 

 to be quite immature; in other cases the pistils are very long 

 and have ripe stigmas while the stamens are still lying bent 

 inwards with closed anthers (Fig. 28, D) ; lastly there are 

 cases where the anthers and stigmas begin to function simul- 

 taneously and as they are at the same level or the anthers 

 are slightly higher than the stigmas and very close to the 

 latter or rise above them, self-pollination will easily be able 

 to take place; I have even repeatedly observed the anthers 

 to be carried in between the stigmas." "Honey is secreted 

 by the inner side of the hypanthium (the shaded part of the 

 1 A similar case is described by Müller in AlpenbL, p. 227. 



