Native: Vegetation 
7 
mind the fact that two localities with the same mean temperature 
for any period may experience quite marked differences in their 
temperature extremes for the same period. 
Mean Annual March of Temperature .—The march of tempera¬ 
ture from month to month throughout the year may be shown 
graphically in a curve (Fig. 3). A steep curve signifies a wide 
temperature range, while a flat curve indicates a narrow range. 
The mean temperature for any month is seen at a glance, as are 
also the warmest and coldest months. 
Decrease of Temperature with Altitude .—The rate of decrease 
of temperature varies with altitude and season. The rate seems 
to be less at high altitudes than at low, and less in winter than in 
summer. The following table shows the decrease in temperature 
per 1,000 feet elevation, for a number of stations in Colorado, for 
the year 1915. The stations compared are within the same drain¬ 
age system. 
