EFFECT ON PROLIFERATION OF FERTILIZING SOIL. 17 
pared with the boll, which would therefore exhibit a more composite 
result of any influential conditions affecting it. 
It is probably true that the increased mortality in squares occur- 
ring during hot dry weather is more directly attributable to the 
absolute maximum temperature experienced than it is to the slightly 
higher mean average temperature prevailing. The observations 
which have been here recorded refer only to conditions found in 
squares which have been attacked by the weevil, but before they 
have fallen to the ground. After squares have fallen the influence 
of hot dry weather in largely raising the percentage of mortality 
wherever the squares become directly exposed to the sun is unques- 
tionably a still more important factor in destroying the immature 
stages of the weevil. 
EFFECT ON PROLIFERATION OF FERTILIZING THE SOIL. 
In accordance with indications shown by some of the examinations 
of bolls made in 1903, it was expected that fertilization of cotton 
might produce a considerable increase in the percentage of cases in 
which proliferation followed injury by the weevil. A test of this 
point required a comparison of a considerable number of varieties 
under similar cultural and soil conditions with check plats unfer- 
tilized for each variety. Tests of this nature were instituted at the 
beginning of the season of 1904. Favorable conditions for such 
observations were also furnished by the field experiment at Calvert, 
Tex., during the season of 1905. Fourteen varieties were there grown 
upon Brazos bottom lands. Each fertilized plat received an appli- 
cation of 400 pounds of acid phosphate per acre. Conditions in all 
plats were similar with the exception of fertilization. 
31022—No. 59—06—3 
