382 KK. P. DEAtTRICK 
poisonous influence of manganese than those that are transferred from germinating pans 
and placed immediately in solutions of manganese. The nature of the medium used in this 
preliminary treatment — that is, whether distilled water, tap water, or full nutrient solution — 
has no visible effect on the resisting power of the plants.” 
The seeds in this second series, consequently, were germinated as before, 
but when the seedlings were about eight centimeters high the endosperms 
were pinched off. This was done to eliminate as much as possible the 
influence of the storage food. The concentration of the nutrient solution 
was but one-fifth of that used in the previous series of cultures. 
The average dry weight of the wheat seedlings at the time of setting 
up the cultures was determined, so that the effect of the manganese solu- 
tions might be the more accurately ascertained. The results are given 
in tables 3 and 4: 
TABLE 3. Wueat SEEDLINGS (ENDOSPERMS REMOVED) GROWN IN SOLUTIONS OF 
MANGANESE Satts. No Nutrients PRESENT 
Increase 
Average or decrease | Relative 
Parts per million of manganese dry weight | im weight | increase or 
(grams) during the | decrease in 
two weeks weights 
(grams) 
SEs eh etree elated Vetta dtm cbs eae ea .0319 .0025 100 
Manganese sulfate 
TDR Rat Te tet se Nek Ss apices en hansen eit ar Se cyyeaC PE a? .0336 .0042 168 
Nan EN © {TR RIOR A WY ae OI er 0304 .0010 40 
TORS ea aed 6 ok LAB ceMRC es EaheyE Ue coe eae .0298 0904 16 
OOF AiR peri ce ane Si Ecco Un pitas ain the pen RE EI .0309 0015 60 
NOOO ete ee REE LR AUST EAD ee ere Lees ate 0258 —.0036 —144 
Manganese chloride 
LON TURNS ck e aT ame MEN Re Spee Soy RRC 8 PSN Reet 0352 .0058 232 
Pas Serer SRM KROME, iC mene Da Rirtete Seen .0342 .0048 192 
LOBES ASR ED Sites Nop Oe betes re coin hs ee eee .0332 .0038 152 
(OO) Rares eine ih Creme oat y eared aise Beat ta pes .0309 .0015 60 
II] O1 0 seater een cea Een 2, eee UR peme  n NaN AUT .0252 — .0042 —168 
Manganese carbonate 
IR US Oe en A SAS ALAR Se hed MaMa A eg 0322 .0028 112 
RRR as re eR ORG, MICO E, tree ena ene Cy 0350 .0056 224 
IU Re en eames Wier Reaed nT AUN US Oa .0297 .0003 12 
T1010 aries es a ot re OE ee te eter oS WL me Ae Ie OR lS at .0349 .0055 220 
