168 F. B. GUTHRIE AND k. HELMS. 
In Nos. 53 and 54 the germination was slightly retarded, 
more so in 55 and 563; very much retarded in 57, whilst 
the seeds of 58 and 59 had not germinated. 
The growth of all was more or less affected. 
On November 21st the plants of pot 52 were growing 
well, though the effect of carbonate of soda was noticeable. 
This was somewhat more marked in 953, whilst in 54 the 
growth was strongly affected, and in 55, 56, 57, 58 and 59 
the plants were all dead. 
The conclusions drawn are the following :—Quantities 
up to ‘1 per cent. carbonate of soda in the soil are tolerated 
by the maize plant, and are without effect upon the ger- 
mination or subsequent growth. °1 per cent. already acts 
as a poison to the growing plant, the effect of which is 
more and more marked up to between ‘25 and ‘30 per cent. 
at which point the plants die. The germination is slightly 
affected by °2 per cent., and °5 per cent. prevents germin- 
ation. 
Experiments with ammonium sulphocyanide. 
Six pots were prepared as in the previous experiments 
with the following quantities of sulphocyanide, and sown 
on October 24th :— 
No. 60, °001 per cent. NH.CNS. 
ay Obs, 002 ‘A ms 
», 62, *003 os af 
» 63, “004 Bi 3 
5 64, O05" |; 9 
9 65, "006 Do)e 29 
On November 3rd, Nos. 60 to 63 had germinated well. 
In Nos. 64 and 65 the foliage had become spotted. 
On November 21st, Nos. 60 to 63 were growing fairly, 
though all showed signs of the effect of the salt, and were 
not so vigorous as the check plants. Nos. 64 and 65 had 
recovered in colour but the growth was somewhat stunted. 
