A. C. Halkel 
'74 
Phyllocactus sp. 
Gram-Molecular Concentration of NaCl. 
•10 
•09 
•08 
•07 
•06 
1st 
2nd 
1st 
2nd 
1st 
2nd 
1st 
2nd 
1st 
2nd 
Read- 
Read- 
Change 
Read- 
Read- 
Change. 
Read- 
Read- 
Change. 
Read- 
Read- 
Change. 
Read- 
Read- 
Change. 
ing. 
ing. 
mg. 
ing. 
ing. 
ing. 
mg. 
ing. 
mg. 
mg. 
(59-3 
68-4 
66-0 
64'9 
70-8 
72-4 
+ 
40-2 
40-5 
+ 
34-7 
36-0 
+ 
83-8 
84-0 
+ 
71-4 
72-2 
+ 
94-4 
9.3-4 
73-3 
72-8 
68-5 
68-2 
— 
56-2 
55 • 2 
-- 
40-7 
39-9 
— 
54 -,3 
55-0 
+ 
29-2 
29-6 
+ 
61-2 
62-9 
+ 
Therefore the osmotic pressure of the cell sap is equal to that 
of a '085 molecular solution of sodium chloride, i.e., to 3‘7 
atmospheres. 
Cereus sp. 
Gram-Molecular Concentration of NaCl. 
•14 
•13 
•12 
•11 
•10 
1st 
2nd 
1st 
2nd 
1st 
2nd 
1st 
2nd 
1st 
2nd 
Read- 
Read- 
Change. 
Read 
Read- 
Change 
Read- 
Read- 
Cha nge. 
Read- 
Read- 
Change. 
Read- 
Read- 
Change. 
ing. 
ing. 
ing. 
mg. 
mg. 
ing. 
ing. 
ing. 
mg. 
mg. 
57-6 
55-8 
48-7 
47-5 
53-1 
52-3 
346 
35-1 
+ 
58-2 
59-5 
+ 
64-0 
65-3 
+ 
84-6 
85-0 
+ 
86’3 
86-6 
+ 
93-1 
92-8 
— 
75-0 
74-4 
36-3 
35-1 
— 
91-7 
91-1 
— 
66-1 
65-3 
— 
53-7 
53-9 
+ 
62-3 
63-3 
+ 
51-3 
52-3 
+ 
63-2 
63-7 
+ 
74-0 
74-3 
+ 
52-0 
51-3 
— 
52-5 
51-5 
330 
31-7 
— 
59-7 
59-6 
63-5 
63-0 
20-7 
21-2 
+ 
430 
43-4 
+ 
Osmotic pressure of cell sap taken to be same as that of a •! 15 
molecular solution of sodium chloride, i.e., to be 5 atmospheres. 
Crassula Inciea. 
Gram-Molecular Concentration of NaCl. 
•09 
•08 
•07 
•06 
•05 
1st 
2nd 
1st 
2nd 
1st 
2nd 
1st 
2nd 
1st 
2nd 
Read- 
Read- 
Change. 
Read- 
Read- 
Change 
Read- 
Read- 
Change. 
Read- 
Read- 
Change. 
Read- 
Read- 
Change. 
mg. 
mg. 
mg. 
mg. 
mg. 
ing. 
ing. 
mg. 
mg. 
mg. 
65-7 
64-2 
33-0 
32 7 
59-4 
57-5 
75-9 
76-6 
+ 
37-5 
37-9 
+ 
55-9 
56-9 
+ 
55-2 
55*4 
+ 
82-0 
83-2 
+ 
63-3 
61-7 
— 
57-6 
56-9 
74-4 
72-9 
— 
60-8 
61 - 3 
— 
53-2 
51-3 
— 
57-7 
60-0 
+ 
60-8 
61-1 
+ 
Osmotic pressure of sap equals that of a '065 molecular 
solution of sodium chloride, i.e., is equal to 2'9 atmospheres. 
On examining these results it will be seen that there is a 
considerable range of pressures obtained for the different plants. 
The osmotic pressure of a plant of Salicornia raniosissinia from the 
