I30 UNIVERSITY OF COLORADO STUDIES 
spreads out and permits the formation of broad meadow land. Here 
the stream accompanied by a fringe of trees and shrubs takes a meander- 
ing course. The meadows studied were at an altitude of about 7,000 feet 
and hence belong definitely to the foothill zone. In fact the plants of 
rocky hills and slopes are as above noted distinctly of the foothill type 
and not montane. The meadow plants, however, are much like those 
of the meadows in the montane zone. The most characteristic plant 
is Polygonum bistortoides, a species which extends up to the alpine 
summits of the main range. The willows along the stream-banks also 
are species which range up rather than down. This coming down of 
plants of colder regions into the lower altitudes is to be expected in 
meadows where the soil does not warm up as in dry situations. The 
same condition of affairs is well known in the glacial ponds and swamps 
of the Mississippi region. 
PARTIAL List OF PLANTS OF THE MEADOW FORMATION 
DomINANT SPECIES 
Polygonum bistortoides Various sedges and grasses 
Less ABUNDANT SPECIES 
Mentha penardi Mertensia ciliata 
Collinsia parviflora Mimulus langsdorfi 
Dodecatheon radicatum Achillaea lanulosa 
Plantago tweedyi? Fragaria americana 
Equisetum arvense Viola canadensis rydbergii 
Heracleum lanatum 
Summary.—For purposes of reference the material of-the foregoing 
pages may be summarized briefly. The paper gives an account of a 
botanical reconnaissance of a part of Larimer County in northern 
Colorado. The district embraces about 150 square miles and includes 
foothill country to the west and a region of sedimentary ridges and 
valleys to the east. Altitudes vary from 5,500 to 7,500 ft. The physiog- 
raphy, climate and soil of the area are discussed with reference to the 
growth of plants and certain localities of special botanical interest men- 
tioned. The plant formations are then considered and classified as 
follows: Cercocarpus Scrub Formation, Valley Grassland Formation, 
Upland Dry Grass Formation, Canyon Forest Formation, Foothill 
Sagebrush-Grassland Formation, Foothill Forest Formation, and 
Meadow Formation. ‘There is a discussion of the limits and character- 
