2io Smith and Butler. — Relation of 
those growing in solution F. The plants which received potassium after 
a lapse of three days were healthy, but much smaller than those in the full 
nutritive solutions, and their root system was poorly developed and dull white 
in colour, the secondary roots being short and stubby. Altogether, the tops 
appeared to have benefited by the addition of potassium more than the 
roots. The plants deprived of potassium for six days were markedly 
stunted and showed all the symptoms of potassium starvation. The plants 
growing in the absence of potassium for nine and twelve days respectively 
Table XXII. Effect of delayed additions of potassium on amount and dis- 
tribution of potassium in Blue stem Wheat plants grown in water culture. 
- 
Nutritive solution 
used. 
No. of 
plants. 
Amount of potassium 
in 
rops. Roots. plants 
Potassium 
utilized per 
gramme of dry 
matter 
formed. 
Tops. Roots. 
Ratio of 
potas- 
sium 
content 
of tops 
to roots. 
Total 
potas- Potassium 
sium absorbed 
utilized from the 
per nutritive 
gramme solution 
of dry by one 
matter plant, 
formed. 
Mg. 
Mg. 
Mg. 
Mg. 
Mg. 
Mg. 
Mg. 
Mg. 
Solutions A and F, 
combined. 
20 
142.30 
47-6o 
189-90 
65-62 64.02 
I -02 
65- 2 3 
9-39 
Solution F, less 
potassium. Potas- 
sium added after 3 
days. 
20 
54 - 5 ° 
tn 
OS 
O 
0 
6 
64-37 63.45 
1 
1. 01 
63.92 
3-39 
Solution F, less 
potassium. Potas- 
sium added after 6 
days. 
20 
41.10 
10.10 
51.20 
58.21 49-85 : 
1. 16 
1 
56-31 
2.44 
Solution F, less 
potassium. Potas- 
sium added after 9 
days. 
20 
18.50 
4-60 
23.10 
42.86 42.75 
1. 00 
42.84 
1.04 
Solution F, less 
potassium. Potas- 
sium added after 12 
days. 
20 
i. 4 - 4 ° 
3 - 9 ° 
18.30 
32.48 32-64 
o -99 
32.64 
0.80 
Solution F, less 
potassium. 
20 
3.20 
0.80 
4.00 
7 - 7 2 
6-95 
1. 11 
7-63 
0.09 
had apparently failed to obtain any benefit from its addition : like the 
plants growing entirely in the absence of potassium, they were withering. 
The differences in the behaviour of the plants already well marked ocularly 
are more fully brought out when we study the data presented in Table XXI. 
It will be noticed that while the plants grown in solutions A and F show 
virtually the same total dry weight, they differ slightly from one another in 
the relative distribution of it. The root development in solution F is not 
quite as strong as in solution A. 
