Mar. a4 , vn Temperature and Evaporation on Aphis pomi 
971 
The evaporation records were obtained by means of a “ nonabaorbimr” 
Eflfr ^ 2) Simikr to instruments SIS X 
ar^P ? t 0 u Stu< ? ies by vanous workers during recent years Stand¬ 
ardized, spherical, porous, porcelain cups were obtained from the “Plant 
Fio. 1.—Cage used in rearing aphids. 
World,’’ and results as here given should be comparable with results 
obtained elsewhere 5 by means of similar instruments 
Observations were made daily at 9.30 a. m. The amount of 
evaporation was determined by filling the evaporimeter at this time. 
27976—23-1 
