I From the Bulletin of the Torrey Botanical Club, 41 : 483-503- 3° O *9**-] 



Notes on Rosaceae — 



Per Axel Rydberg 



DRYAS 



Little has been added to the knowledge of this genus in the last 

 eighty years. Only one species has been added, Dryas tomentosa. 

 Farr. 



Dryas integrifolia Wahl. Many authors regard this as merely 

 a variety of D. octopetala, as intermediate forms are met with, 

 but these have only been found where the two species grow to- 

 gether and are probably all of hybrid origin. Nathorst* was 

 inclined to regard these forms as hybrids, but he did not call 

 them by a hybrid name, denoting them as D. octopetala f. inter- 

 media. Hartzf held the same opinion, but apparently by a slip 

 of the pen called them D. integrifolia intermedia Nathorst. This 

 hybrid has also been collected in Alaska at Orca, Prince William's 

 Sound, 1899, Coville & Kearney iiqi. 



Dryas octopetala L. Hartz, loc. cit., admitted several varieties 

 of Dryas octopetala, viz. var. minor Hook., var. hirsuta Hartz, and 

 var argentea Blytt. The last one of these seems to be furthest from 

 the type, but by no means deserving specific rank. Simmons 

 described a similar form of D. integrifolia, viz. D. integrifolia 

 canescens. 



Dryas tomentosa Farr. This species is closely related to D. 

 Drummondii and perhaps not distinct. It may be only a variety 



* Ofvers. Kong. Sv. Vet. Akad. Hand. 41 1 : 24. 1884. 

 t Medd. Groenl. 18: 321. 1895. 



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