382 BOTANICAL GAZETTE | DECEMBER 
as weak as ;~”,,, the growth was normal, in as strong as 3y5 
a killing strength was not reached. 
Uromyces, from a generalization made in my notebook, grew 
2 : . : 
normally in ,,%,,, not quite as well in 355, and is prevented 
nn 2 e . 
by gzop €xcept in very rare cases, where a single spore grows. 
TABLE II. 
POTASSIUM CYANID. 
Gleeosporium Macrosporium Penicillium Uromyces 
cS ee 
Grew Failed Grew Failed Grew Failed Grew Failed 
n n n n n id 
— 2 2 
: 6400 t $00 : 25600 400 12800 ee 25600 S00 
n 
n n n 
es 3 ‘ate 
’ 3200 - 800 - 50 800 6400 3 G00 
n n n n n es 
I * 2 Y Bacmmcers 
800 I “a t rae 2 aoe 3200 106 
n n n n 
2 2 
400 Too - 200 Z 800 
n 
I 
400 
n 
3 
100 
ee 
* No. 1369. Some grew poorly. 
Tt No. 1363. Nearly all grew to about half normal size. 
Potassium cyanid.— Potassium cyanid was tried upon Gloeo- 
sporium and other fungi, and, notwithstanding its great toxic 
action upon animal organisms, proved comparatively harmless to 
the spores. Starting with ,j%,, on Glceosporium, successively | 
stronger solutions were tried till ,%, was reached without pre 
venting growth. No stronger solutions were tried. 
Macrosporium with potassium cyanid was started at 35600" 
and successively stronger solutions taken till ¥%, was reached. in 
this strength one culture grew poorly and two failed, so that - 
the fatal strength was evidently reached. With Penicillium 45 
proved fatal. Uromyces grew normally till a strength of s%y Was 
reached. In this the growth was much stunted in one culture, 
