416 BOTANICAL GAZETTE [JUNE 
in the periblem and inner plerome still showed normal chromatic 
figures; some nuclei were in the spireme stage, although the majority 
were resting; cellular activity, as expressed in division, had prac- 
tically ceased. 
A comparative estimate of the proportion of cells in course of 
division in each of the several experiments did not show that any 
concentration used had stimulated division; on the contrary, the 
retarding influences, particularly in the more concentrated solutions, 
were very pronounced. The first apparent effect of the toxic solution 
was arrest of nuclear division through inhibition of the activities of 
the achromatic figure. In the early division stages this was soon 
followed by degeneration of the spindle fibers. In the later stages 
of division the failure of cell plate formation was characteristic. 
These phenomena were accompanied or followed by an increase 
in the number and size of the vacuoles in the cytoplasm. The death 
of the cell evidently occurred shortly after this condition was reached. 
It seems probable that the toxic solution penetrates somewhat 
slowly to the inner cell layers, since under its influence the outer 
layers of cells are killed, while in the inner regions not yet visibly 
affected, normal development continues. 
There was no satisfactory evidence of the occurrence of amitosis. 
Double nucleoli occurred as frequently in the cells of the controls as 
in those treated with the copper solutions, a result which, so far 
as these experiments have extended, directly controverts the state- 
ment of WASIELEWSKI (30) that “das erste Kennzeichen, dass ein _ 
Kern sich zur amitotischen Theilung anschickt, besteht in einer 
Verdoppelung des Nucleolus.”’ 
The copper solutions did not cause abnormalities in the develop- 
ment of the chromatic figure. There was no doubling of the normal 
number of chromosomes. Occasionally two daughter chromosomes 
remained attached by their ends for some time after the others had 
left the nuclear plate, apparently forming an attachment between the 
daughter chromosome groups. However, this irregularity was also 
observed in the controls. NEMEC (21) states that treatment with 1 
per cent copper sulfate solution produced binucleate cells in root tips 
of Vicia Faba. After 17 hours’ sojourn under normal conditions 
binucleate cells no longer appeared, and he concluded, therefore, that 
. 
