1896] TOXIC ACTION OF DISSOLVED SALTS 89 
mine the condition of the roots, the general appearance and 
the growth made after the beginning of the experiment 
‘were taken into account. If a much too concentrated solu- 
tion was used a plainly abnormal aspect was usually found. 
In the acid solutions the satiny luster of the normal sur- 
face was lost and a dead-white color was observed, suggesting 
a condition perhaps best described by the word coagulated. 
Although difficult to describe, this condition is quickly detected 
by the observer, and is undubitable evidence of death. An 
instructive discussion of this and other fost mortem symptoms 
has recently been presented by Paul Klemm. The radicles 
killed in colored solutions, as salts of copper, iron, cobalt, etc., 
took on more or less decidedly the color of the. medium. Some 
radicles after death assumed an unusual transparent appearance. 
This was the case with those in potassium hydroxide, and in 
mercuric cyanide, potassium ferro and ferricyanide, hydrocyanic 
acid and potassium cyanide. 
Another evidence that death has taken place is seen in the 
flabby condition following the loss of turgor pressure. This, in 
the extremely dilute solutions here used, could in no case be 
due to the osmotic properties of the solutions, and it would be 
still more improbable that, after fifteen to twenty-four hours in 
the medium, the flabby appearance could be due to this cause. 
Turgor accommodation in a normal root, when placed in a solu- 
tion osmotically equivalent to those here used, would take place 
very soon,” and living roots would be turgid. 
Another indication of the condition of the radicles was sought 
in the changes in length occurring after the beginning of the 
experiment. In strongly toxic concentrations where death 
occurred very quickly, the accompanying loss of turgor left the 
roots shorter than at the beginning of the experiment. As the 
solutions were increasingly dilute but still, within the time limit 
of our experiments, fatal, various amounts of growth were found 
*3 Paul Klemm, Desorganizationserscheinungen der Zelle. Jahrb. f. wiss. Bot. 
28: 30. 1896. 
True, ibid. 382. 
