326 RYDBERG: PHYTOGEOGRAPHICAL NOTES 
sandhills in the so-called ‘‘ Parks” of Colorado and in some of the 
broader river valleys. Most of the species characteristic of both 
are also found on the Great Plains and are such as have migrated 
along the rivers to higher altitudes. The following species are 
components of the flora. None of these are transcontinental or 
common to the Rockies and the Canadian Zone. A few are 
common to the Rocky Mountains and the Sierra Nevada Region, 
but most of them are endemics, either of the Great Plains or the 
Great Basin, or both. 
Eriocoma hymenoides Gayophytum intermedium 
Muhlenbergia pungens Gayophytum ramosissimum 
Stipa speciosa Gayophytum racemosum 
- Oryzopsis Webberi Nuttalha multiflora 
Sitanion elymoides — Nuttallia densa 
Arenaria confusa Nuttallia speciosa 
Arenaria polycaulos Cryptantha Torreyana 
Peritoma serrulatum Lithospermum multiflorum 
Epilobium paniculatum Helianthus petiolaris 
M. ROCK SLIDES 
The rock slide flora of the upper Montane Zone resembles that 
of the Subalpine, which has already been described.* In lower 
altitudes the following species appear, all of which are endemic to 
the Southern Rockies except Viola biflora, which is found also in 
Europe. 
Elymus ambiguust Polemonium confertumt 
Aquilegia saximonanat Polemonium mellitum}t 
Aragallus Halliit Polemonium Brandegeit 
Limnobotrya montigenat Pentstemon stenosepalust 
Viola biflorat Senecio Fendlerit 
Pseudopteryxia anisatat Senecio amplectenst 
Pseudopteryxia aletifoliat Senecio canovirenst 
NEW York BOTANICAL GARDEN. 
* Bull. Torrey Club 44: 453. 1917. 
