26 BOTANICAL GAZETTE [) ANUARY 
The toxic limit is about the same concentration (42/100 to 3/100) 
as with lead nitrate; there is very little toxic effect shown above 
gn/1o0o; the region of acceleration is at 2n/1000. 
3n/10oo are dead, 
while 27/100 has maintained its rate of growth almost equal with 
the control. The death limit is therefore very clearly pointed out. 
On the other hand, acceleration is very vague. 
The solution series (fig. 16) represents a series beginning at the 
left with 72/1000, 6n/1000, 5/1000, etc., as in figs. 14, 15. Here 
ie 
TABLE VI 
AGNO, SERIES IN sort. AVERAGE OF THREE EXPERIMENTS 
H.O eae | ee ae | ae | oe) | eee 
: 10000} 5000 | 1000 | 1000 | 1000 e00 | 1000 | 1900 | I00 100 nes 
ength of sprout, cm.| 20.64 | 21.50 | 22.48 | 22.58 | 21.44 | 20.06| 19.68 | 19.74 | 17.82 | 16.42 | 15.50 | 13-22 2.55 
Total transpiration, gm..| 61.4 | 62.2 | 66.9 |67.9 |65.6 |57.6 |54.0 | 53.2 | 51.1 | 42.1 | 36.1 | 30-5 
dal oe eet ea oe ee ie ae ae [oe 1 | | ee 
In fig.14isrep- yo 7 
resented a_ series 
of 23 cultures six hans 
days old, in quartz, —/so00 
running from left |.) 
to right 2/10, 
gn/100, 8n/100, 3/19 
ete., aS in the case~ gi7iso | 
of CuSO, and | / hee 
Pb(NO,),. Asmall = ij i 
amount of elonga- 8%/r00° ; j = 
tion has taken place oy/1000 yy Lael 
in 4n/100,consider- F/G fo ee ae 
able in 3n/100,and | tL. a ae Bee 
in 2n/100 the 2/100 Ae} + —+— 
growth is about ,,,.,, we a 
normal. In fig..15 Se og ee 
the same setics ig 2" ie Se és 20 a 
12 days old. aa : fe Fae a 1159 
Here 4n/10o and om ees Sorte ee hs ne ai 
IG. 13.—Silver nitrate series in soil. Average of results 
