14 Canadian Record of Science. 
mean temperature as they, in a northwestward direction, 
cross the continent. Others again may find the dry prairies 
east of the Rockies and the dry interior plateaus of British 
Columbia equally congenial. Much more information is, 
however, yet needed. 
The plants hereunder, are examples of the group :— 
Myosurus aristatus, Benth. Grindelia squarrosa, Dunal. 
Vesicaria Ludoviciana, D. C. Chrysopsis villosa, Nutt. 
Silene Menziesii, Hook. Helianthus annuus, L. 
Astragalus aboriginum, Rich. Artemisia dracunculoides, Psh. 
.Potentilla Hippiana, Lehm. Troximon glaucum, Nutt. 
Crataegus Douglasii, Lindl. Androsace occidentalis, Pursh. 
(nothera albicaulis, Nutt. Comandra pallida, D. C. 
Sedum stenopetalum, Pursh. Euphorbia serpyllifolia, Pas. 
Rocky Mountain GRovup. 
Further enquiry into the range, as well eastward of the 
mountains, as in British Columbia, of the species presently 
referable to this group, is needed before the group can be 
definitely determined. Some of the plants specially refer- 
able to it can be classed as boreal, and are known, to the 
northward, to fringe outward beyond the mountains into 
the Mackenzie River district, and even towards the coast. 
There are also some alpine plants, entirely confined in 
Canada to the Rocky Mountains, and there are others— 
arctic species—which, whilst they have a considerable range 
along the arctic coasts between Hudson Bay and Alaska, 
seem to use the mountains as a ridge along the higher sum- 
mits of which they extend into latitudes far to the south- 
ward. 
The following plants presently exemplify the group, in 
so far as their range is presently known :— 
Clematis Douglasii, Hook. Cymopterus terebrinthus, T. & G. 
Aquilegia flavescens, Wats. Musenium tenuifolium, Nutt. 
Lychnis elata, Watson. Brickellia grandiflora, Nutt. 
Astragalus glabriuscula, Gr. HKrigeron bellidiastrum, Nutt. 
Oxytropis viscida, Nutt. Cnicus eriocephalus, Gray. 
Rosa Fendleri, Crepin. C. foliosus, Gray. 
Parnassia fimbriata, Koenig. C. Hookerianus, Gray. 
Bupleurum ranunculoides, L. Populus angustifolia, James. 
