144 BOTANICAL GAZETTE | AUGUST 
which were killed by the cobalt solutions were also very brittle 
and rigid, the same as in the nickel solutions. : 
The results obtained for the seedlings of Zea Mais in the dif- 
ferent solutions are given in the following table: 
ZEA MAIS. 
. 1 1 
pate aad Cobalt. reas | xsov | atoo | reso | re00e ia 
mol, mol. mol, mol. mol. 
ia mm 
NiSO, Ist 24 hours oan Bisa 2 mm 3 m 45 mm rt 
aa: 34 hoursi:. .. iy ae oh Re ‘ 
‘ : “ “ 17. f 
Ni(N Ist 24 h’rs oS +. a 555 4 fe 
MNOo)s td 24 h'rs| .. Age o a a 16.5 
CoSO Ist 24 hours 2.5 mm ] ™m 20.5 “ 27 “ : ie 
* (2d 24 hours} .. a 16 ee es . 
Co(NO)s es 2 * | 3.25" | 22.5" | to 4) oe . 
2d 24 h’rs ky a 19 “ 34 ‘“c ae z9 
aa 
___ and the 
The seedlings were set first in ¢¢y9) rxh00 B5eo0 * 
srz00 Zram-molecule solution of NiSO,. The first three s 
growth for the first twenty-four hours but none afterwards, 
those in the last solution grew for the entire period of the ~~ 
ment. For the Ni (NO,), only the three solutions shown 11 ~ 3 
first table were used; in the first two growth occurred during 
the twenty-four hours, but none afterwards, so that the killing | 
point for the nickel salts may be considered the a5o00 gree : : 
molecule solution. : 
n " 
howed 
while 
per- 
soluti ae, 
nS, rgoo and 5,1, gram-molecules. 
grew for the first twenty-four hours, but no 
resulted at the second measurement. The killing point oe 
cobalt salts is thus placed at the ,,',, gram-molecule solution: | 
One point which must be noted in connection with all of 
experiments with the nickel and cobalt salts is that in We 
every case a certain amount of growth resulted during the oo 
