RYDBERG: PHYTOGEOGRAPHICAL NOTES 307 
B. EASTERN SPECIES, EXTENDING INTO THE NORTHERN ROCKIES 
ONLY 
I. SPECIES REACHING AT LEAST THE YELLOWSTONE REGION 
Carex Richardsonu Phaca americana 
Carex eburnea Hedysarum americanum 
Heuchera hispida 
Of these, Heuchera hispida and Phaca americana even reach the 
Black Hills and western Nebraska. 
2. SPECIES EXTENDING ONLY TO NORTHERN MONTANA OR IDAHO 
Carex tenera — Chiogenes hispidula 
Carex pedunculata Melampyrum lineare 
Parnassia palustris (Eur.) Thelypteris Robertiana (Eur.) 
Mitella nuda Dryopteris cristata (Eur.) 
3. SPECIES LIMITED TO THE CANADIAN ROCKIES 
Trees 
Picea canadensis Picea mariana 
Shrub 
Salix pellita 
Herbs 
Carex atratiformis Primula mistassinica 
Vagnera trifoliata Petasites palmata 
Coptidium lapponicum (Eur.) _—Pteretis nodulosa 
Ribes glandulosum Dryopteris intermedia 
Geum perincisum 
_ Of these, Picea canadensis and Pteretis nodulosa are found also 
in the Black Hills. 
C. Rocky MouNTAIN SPECIES WHICH HAVE EMIGRATED EAST- 
WARD 
The following plants have extended their ranges as far east 
as eastern Minnesota, western Ontario, upper Michigan or Hudson 
Bay. 
Shrubs 
Rosa Bourgeauiana - Amelanchier alnifolia 
