220 



PITTONIA. 



separated; and this was the view entertained by Douglas, 

 Nutfcall and others who had a field acquaintance with tlie 

 northwestern shrubs, and an appreciation of the geographical 

 side of the question. But even the herbarium men should 

 have discovered that S. heliilmfoUa in the fruiting state has a 

 good character which entirely fails in all the American plants 

 which have passed under that name. I refer to the narrow 

 and reflexed calyx-lobes. Kecognizable by this mark, I have 

 good specimens of this species from the Porcupine Eiver iu 

 the interior of northern Alaska; but no other American speci- 

 mens that I have seen match these, excepting those of a new 

 species characterized below. 



^ SriR.EA CORYMBOSA, Raf. Prec. Decouv. 36 (1814). Occur- 

 ring in the Allegheny Mountain region only, and ranging 

 from Pennsylvania to Georgia, thus belonging to a climatic 

 belt as different from that of northeastern Asia as can be 

 found outside the tropics; completely isolated from even the 

 North American plants most allied to it— for the distance 

 between its habitat and that of the following species is some 

 two thousand miles— it must have been by ignoring alto- 

 gether the geographical consideration that any authors became 

 persuaded that the S. corymbosa of Eafinesque could be a 

 synonym of S. betidcvfolia. It is really very distinct; though 

 the usual analogy between East Asian and East American 

 related species of plants holds here; for the Iq florescence is 

 pubescent in these two, while it is perfectly glabrous in all the 

 correlated West American plants. S. corijmhom has, how- 

 ever, those broad and merely spreading, never reflexed, calyx- 

 teeth, which constitute a distinguishing feature of all the 

 endemic American species when compared with the Siberian 

 type. The large and long leaves are another good character 

 for S. covijmhosa. Doubtless also in the mode of growth 

 another mark may be found by those who are privileged to 

 "*"-■'" the species in its native wilds. For my only fruiting 



study 



n 



