1908} HOLM—ALPINE GRAMINEAE 423 
elevations. According to this author 58 of these species occur also 
in the European and Asiatic mountains, or in high northern latitudes 
of both hemispheres. He enumerates 9 Gramineae. Among the 
168 species of flowering plants I collected in this region only 17 belong 
to the Gramineae. The largest family is the Compositae with 25 
species; then follow the Cyperaceae with 20, and then the Gramineae. 
Just above timberline the vegetation is luxuriant to the full extent of the 
word, and a number of very different plants abound in the willow- 
thickets along the mountain brooks; at higher elevations we may 
observe a rich vegetation on the slopes, especially near the snowbanks; 
but when we cross the bowlder fields we meet only with a very scant, 
often extremely poor, vegetation. Among the plants which were 
observed on the very summit of these mountains may be mentioned 
Poa Lettermanni, Festuca ovina supina, Claytonia megarrhiza, 
Stellaria umbellata, etc., but none of the Cyperaceae. It seems as if 
the Gramineae are able to thrive at very high elevations, judging from 
the various records of alpine plants in Europe and Asia, as will be 
shown later. It might be stated at the same time that some of these 
are among those that occur in the most northerly points; for instance, 
Alopecurus alpinus at 83° 4’, Poa flexuosa at 82° 50’, and Festuca 
brevifolia at 82° 27’. 
In the accompanying Table (I) I have enumerated the alpine 
species of Gramineae, which I collected on the following mountains: 
Long’s Peak, James’ Peak, Pike’s Peak, Mt. Elbert, Mt. Massive, 
Mt. Kelso, Gray’s Peak, and along the headwaters of Clear Creek. 
To these may be added Deschampsia calycina Presl. from the summit 
of Gray’s Peak, collected by B. H. Surra; and Poa Pattersoni Vas. 
from mountains near Gray’s Peak, collected by H. N. PATTERSON. 
The altitude where these alpine species occur lies between 335° 
and 4300™, Agrostis canina var., A. varians, Avena Mortoniana, 
Poa flexuosa, P. gracillima, P. Fendleriana, P. Lettermannt, fe. 
Pattersoni, P. alpina, Festuca ovina supina, Deschampsia calycina, 
Agropyrum Scribneri, and A. violaceum are in Colorado confined to 
the alpine region. The remaining species, on the other hand, were 
also observed at lower elevations, from the aspen zone (about 2500™) 
to the spruce zone (about 3100™). Phiewm alpinum, for instance, 
descends to the aspen zone on Long’s Peak, where’ it is very frequent 
