1906] SHANTZ—VEGETATION OF THE MESA Fu 
at a depth of 15°™, at the surface of the soil, on the plant, at 10°™ 
above the soil, and finally 1™ above the surface. A constant record 
was taken by means of a thermograph, and the records of the Weather 
Bureau were also made use of to check-the results thus obtained. 
GARDEN OF THE Go 
sonruys ov 
SCALE—4CM TO | KM. 33° $0’ 
Map. ‘ 
In the measurement of light the writer has used the ordinary 
photometric method, but has used the standard derived from the 
candle power. Solio paper was exposed to a standard candle for 
