Southern Park Mountain District. 557 
11,500 feet in open woods, which show no trace of fire. Where the original 
timber has been destroyed it forms an "almost pure growth. 
Many species are associated with this tree, viz: Rosa m: an je Poa Ser 
(= P. nemoralis), Anemone globosa (= A. multifida), Festuca Thurberi (= F. scabrella), P: 
laris procera, Helianthella Parryi, Pentstemon glaucus, Frasera erg, Rodbeckie _ er 
obtusata, Calochortus Gunnisoni, Castilleia confusa, Gentiana Parryi, G. acuta, &c. In the Davis 
mountains in Texas a thicket of Populus tremuloides is Sr along the northeast base 2 a high 
cliff near a Peak and indicates a mere trace of a formation developed more extensively 
to the northeas 
ag Formation. The meadow-thicket formation consists of several 
willows, such as, Salix Geyeriana, S. chlorophylla, 5. glaucops, 5. Bebbiana, S. 
monticola, Betula glandulosa, Potentilla fruticosa, 
The vernal aspect is due to Thalietrum alpinum, Carex aurea, Mertensia lateriflora and in 
summer grow Deschampsia caespitosa, Crepis runcinata, Lilium montanum, Thlaspi Be 
Cerastium oreophilum. The autumn vegetation consists of Aster Geyeri, Gentiana acuta, Mert 
ciliata, Saxifraga hirculus. 
Ouercus-Cercocarpus Formation. This is a foothill formation in the shape 
of a thicket along the eastern base of the mountains and down the ridges 
and gullies far out on the plains. Cercocarpus parvifolius, Rhus trilobata, 
Quercus Gambelü, O. utahensis (= O. stellata var. utahensis), Prunus demissa 
constitute the facies. 
The species mentioned by CLEMENTS in association are numerous. Only a few are given 
below. Malvastrum coceineum, Oxybaphus (Allionia) hirsutus, Mentzelia nuda, Chrysopsis villosa, 
aura coceinea, Castilleia integra, Phacelia glandulosa Verbesina encelioides, Mirabilis oxybaph- 
oides, Woodsia mexicana, Notholaena Fendleri, while Bali Bes Holodiscus dumosus, Ribes 
cereum, R. leptanthum, R. pumilum are among the prineipal shru 
2. Meadows, Lakes and Bogs. 
Meadow- and Swamp Meadow Formation. The plants of this formation 
cover the filled-in beds of old lakes and they resemble in the Flathead Valley 
and elsewhere swamps with similar edaphic situations in the eastern United 
States. Near the head of Ross Lake, for example, is a sphagnum meadow 
in which grow Menyanthes trifoliata, Drosera eael, Potentilla palustris, 
Eriophorum polystachyon, and Betula pumila®). — Other large meadows show 
this combination. These meadows are usually submerged during the spring 
and early summer months, when the melting snow of the mountains to the 
eastward swells the streams. These meadows, as previously stated, show a 
gradual encroachment of Picea Engelmanni upon them. 
The meadow flora in the Vellowstone Park (7,500—9,000 feet) (2300—2740 m) consists of 
Stellaria umbellata (= Alsine baicalensis), S. (A.) longipes, S. borealis, Saxifraga punctata, S. inte- 
grifolia, Valeriana edulis, V. sylvatica, V. septentrionalis, Potentilla dissecta, P. gracilis, P. 
ı) BaıLev VERNon: Biological Survey of Texas. North American Fauna, No, 25, U. 5. 
gen wer 1905: 38. 
) WHrTForD loc. eit. p. 195. 
