256 Dr. DaunENY on the Degree of Selection exercised by Plants, with regard 
accuracy. 1124 grains of scarlet kidney-beans (Phaseolus multiflorus) were 
sown in a box containing about 290 lbs. of powdered sulphate of strontian, 
which had been ascertained to be free from alkaline matter, but to contain 
2 per cent. of carbonate of lime, and about 4 per cent. of alumina. The box 
was placed in an open situation, exposed to sun and rain; and when the plants 
reared from these seeds had come to maturity, they were cut down and burnt. 
An account was then taken of the weight of the ashes remaining after the 
combustion had been completed, and of the fixed principles obtained from 
them, first, by lixiviation in water; secondly, by digestion in nitric acid; 
and thirdly, by treating the remainder with an alkaline carbonate, and then, 
again, with the same acid as before. A similar process was gone through with 
the same quantity of the kidney-beans as that of which the plants examined 
had been the produce. 
The following will present a tabular view of the results obtained. 
Soluble portion of these ashes 
: í In nitric acid, 
Subject of the hen acien Weight of 
Experiment. É its ashes, ; 
I Without | After having been acted upon by 
aris ss an alkaline carbonate. 
reatment. 
Earthy Earthy 
phosphate. sulphate. 
Seedsof Phase- 
olus mulio- | ere ae ka 106 6:7 0:67 0 0 
rus, 1124 grs. 
In a soil chief- 
Ditto ly composed 
1194 er of sulphate of 283 11°3 131:5 31:0 2:8 
T strontian, in | 
a garden ...J 
Now the aqueous solution represents the amount of alkali combined either 
with the phosphoric or carbonic acids; the solution in nitric acid without pre- 
vious treatment, the earthy carbonates and phosphates*; that in nitric acid, 
after the action of an alkaline carbonate, the earthy sulphate, with that por- 
* The difference in the quantity of lime to be inferred from 100 of phosphate and 100 of carbonate 
was only as 53 to 56. 
