150 CONTRIBUTIONS TO WESTERN BOTANY 
took but a few minutes for the driers to dry in the baking sun. It had to 
be done daily to prevent specimens from moulding or turning black. 
For driers we now use double-faced corrugated cardboard cut into 
sheets 12 by 18 inches. When tightly strapped down, they seldom need 
changing in the usual weather of the deserts, if the bundles are kept out 
in the sun and wind. I have gone for weeks without changing these 
driers. It is best to keep fleshy plants (such as succulents) in a spearate 
press with extra driers and for frequent changing. I usually take along 
300-400 driers for a trip. When the weather is wet there is nothing to 
do but change driers even if they have to be dried over a fire, which is 
a long and tiresome job. But in all my botanizing I have had to dry my 
and leaves usually lie flat and lifelike, with only the occasional special 
arrangement of a leaf. I pile the empty quires of paper on the filled 
sheets, strap up my portfolio, and trot along for another picking. 
