408 BOTANICAL GAZETTE [DECEMBER 
cannot suffice to explain the very high turgor of the plants 
grown in it (6). When Ca(NO,), was replaced by CaSO, the 
osmotic power was reduced, but here, too, the turgor surpassed 
the normal. 
The results given in this table tally very well with those 
obtained on Phaseolus, Pisum, and Sinapis, as far as the latter 
were carried out, the only difference being in the low turgor of 
buckwheat grown in cultures free of nitrates. In another series 
the turgor of the stems grown in nitrate-free cultures rose to 2-2.5 
per cent., while in normal stems it was 2.5 per cent., both tested 
before there was any marked difference in growth. It certainly 
looks as though the turgor fell because the nitrates were absent, 
but no such tendency could be detected in any plant tested 
except the buckwheat. The turgor of 5 was distinctly higher 
than that of 1 before any difference was noticeable in their 
growth. The last three cultures (6, 7, and 8) were stunted in 
growth by the end of the second week, which explains their 
extreme turgor. 
Zea Mays. Two series of cultures were carried through. For 
the first, dating from January 16, the cultures were made as 
described under Phaseolus. 
1. Normal 
Feb. 6 Feb, 18 March 6 March 13 April 13 
Stem turgor 2.5% 2.5% 3% 3-3-5% 
length 30-™ 43" 60c™ 6o0°™ 
ae turgor 2% 2% 2% 2-2.5% 
2. Distilled H,O. 
Stem turgor 1.5-2% 22.5% 1.5-2% 1.5% 1.5—26 
length 29" 34°" 47°™ 50°" 
noe | turgor 1.5% 1.5% 11.5% 1.5% 11.5% 
3. K replaced by Na. 
Stem turgor 2% 2-2.5% 2.5% 2.5% 
length 320" 38°" 4r™ 43° 
Root } Gs 1.5—24 24 2% I 5-2% 
4. Ca replaced by Na. 
Stem turgor 3% 3% 3.5% dead 
_, § length 340" 36" 54c™ dead 
— turgor 2% 2% 2-2.5% 
