| ; 
: 
. 
% THE EFFECT OF HYDROCYANIC ACID GAS UPON 
GRAINS AND OTHER SEEDS. 
C. O. TOWNSEND. 
(WITH SIX FIGURES) 
INTRODUCTION. 
THE experiments which form the basis of this paper were 
undertaken more than two years ago for the purpose of deter- 
mining the effect of hydrocyanic acid gas upon the germination 
of seeds. The necessity for the work arose from the rapidly 
increasing use of this gas in the destruction of insect pests 
| infesting stored grains and other seeds. Since these experi- 
ments were begun a number of the largest flour mills in this 
country and Canada have been fumigated for the destruction of 
insects without removing the thousands of bushels of grain stored 
' in the mills, and likewise numerous barns and granaries filled 
with grain have been fumigated for the same purpose. Since 
) the grain thus fumigated may be used either for seed or for food, 
it is important to know whether or not the germinating quality 
of the grain has been injured and whether grain thus treated 
would be injurious for food. A preliminary account of the 
experiment in regard to germination of seeds after treatment 
with hydrocyanic acid gas was read before the Botanical Section 
| of the A. A. A. S. at the Columbus meeting and subsequently 
| published. 
The use of hydrocyanic acid gas for fumigating purposes is 
of comparatively recent origin, having been introduced by the 
2. S. Department of Agriculture, Division of Entomology, in 
1886, for the fumigation of orangetrees. It was first used for the 
fumigation of greenhouses by Dr. A. F. Woods,’ Director of the 
i *TOWNSEND: “The effect of hydrocyanic acid gas upon the germination of 
| seeds.” Sci. Amer. Suppl., no. 1248, 2 D. 1899. 
| *Woops: The variable effects of hydrocrani acid gas on plants and animals. 
Rep. Soc. Plant Morph. and Physiol., Am. Nat. 1899. 
Igor] 241 

