T9I0] SLOCKBERGER—TOXIC SOLUTIONS AND MITOSIS — 409 
contained other than resting nuclei. After 69 hours’ exposure to 
this concentration the older periblem cells were still more enlarged 
and the outer ones were disintegrating. A few of the inner periblem 
cells showed division stages, none of which were later than early 
anaphase. 
The cells of the root tips treated with /190,000 for 44 hours 
differed little from those in n/70,000 for the same length of time. 
Fic. 1. Proliferated cells of root tip grown in dilute copper sulfate solution.— 
Fic. 2. a, cells of root tip of Vicia Faba after 96 hours in distilled water; 6, the same 
after 46 hours; c, Lu pinus albus 69 hours in distilled water. 
After 72 hours there was no division, and the periblem cells were 
frequently enlarged. : 
In the outer periblem of the material treated with n/100,000 for 
43 hours, a few cells occurred containing division figures. In the 
inner periblem many nuclei were in the spireme stage and the meristem 
area was especially active. In these inner cells the achromatic 
figure appeared to be normally developed, but in the outer layers the 
cells were more or less vacuolized, and the spindle fibers were degener- 
ating. In 93 hours this condition had spread to all the cells. 
Approximately similar conditions occurred in the radicles treated 
in the concentrations 2/140,000 and n/150,000. In 93 situa prac- 
