170 F. B. GUTHRIE AND R. HELMS, 
strongly affected, the leaves in 71 having a bleached appear- 
ance. In 72, 73, and 74 the leaves were quite bleached 
and the. plants dying. 
It is thus seen that germination is unaffected till the 
amount of chlorate reaches *004%, and that quantities above 
"006% prevent germination. The growth of the plant is 
affected by °0017 and when the amount reaches °004% the 
plant is killed. 
Hxperiments with arsenious acid. 
Six pots were filled and sown on October 24th, the fol- 
lowing quantities of arsenious acid having been previously 
added : 
No. 75, ‘05 per cent. As.O3 
vo Os 3 “a 
BA i Ase?) Me 5 
a. Oy oO a as 
sie Coe. Oe) 5 a5 
7 00, 90 6s “3 
On examining the pots on November 3rd germination 
was found to be unafiected- except in the case of No. 80 in 
which the germination was somewhat retarded. 
On November 21st the growth of No. 75 was very slightly 
affected, the effect increasing in the succeeding numbers. 
In No. 77 the growth was somewhat stunted and more 
markedly so in 78, 79 and 80, though the plants were small 
they looked fairly healthy. 
Three other pots were sewn on November 28th :— 
No. 81, ‘60 per cent. As.Os; 
(h Ole) ws a 
» 80, “80 ss Os 
On December 13th it was found that the germination 
had been affected in all cases. In No. 83, it was very 
‘strongly affected and the plants were very feeble. Above 
