102 BOTANICAL GAZETTE [sucust 
TABLE III 
WHEAT (GROWTH DURING 30 DAys). ALL QUANTITIES GIVEN ARE CUBIC 
CENTIMETERS OF 0.12 m SOLUTIONS 
é Aggregate length} Corresponding : |Aggregate length — 4 
Culture solution of roots per point on curve Culture solution of roots per 
plant i fin (Gig. 3) plant inmm 
Moccia, 5 A ii 2 Gl Se eae 5 
too MgCl 100 MgCl 
10 eer Bee 7°5 B ro Kel Z' ees 7-5 
too MgCl too MgCl 
25 ig tenses 10 c = 2 See 8.7 
too MgCl too MgCl 
go NaCl § 0050 13-7 D on 12.5 
too MgCl, too MgCl, 
too NaCl eee 25 E Kel ee ee 21 
60 MgCl,)...... 60 MgCl 
100 mart 37-5 F g 2 Pas 34 
40: MgCl, o MgCl, , 
too NaCl Rowe tse poe G a KG i Sera 48.7 
MgCl 25 MgCl 
so Neer bo 90 H os ied ne 84 
20 MgCl, MeCl : 
zoo NaCl meee a2 I fa Kel ud eee 99 
15 MgCl 15 MgCl, 2. 
Bes or Pees 140 J ei rc ee 125 
oO MgCl M ] > 
200 heck : veteee 176 K So a9 a f gaecds 152 
MgCl 
oi Nec | nis a6 L 7-5 MgCl, a él 
5 MgCl, MgCl 
t00-MNaCl. $25" val bas M ae 43 See Be 135 
INSU Gao 55 N 7 | ae ee 66 
Distilled water, 725 mm 
In algae I have found that MgCl, is much more strikingly antago- 
nized by KCl than by NaCl. a 
The experiments with calcium show a more marked antago : 
nism than any of the other cases. We find that Ca is antag- — 
onized to a slightly greater degree by K than by Na (table IV 
and jig. 4). 
Similar results were obtained with algae, liverworts, Equisetum, 
and some fifteen genera of flowering plants. 
From the facts here set forth it is clear that in their toxic and 
