402 BOTANICAL GAZETTE [JUNE 
sulfate upon cell processes in certain plants, including Spirogyra, 
Tradescantia, Phaseolus, Lupinus, Vicia, Pisum, Allium, and Larix. 
The published accounts of these studies show a general agreement 
as to the production of certain abnormalities in cell and nuclear devel- 
opment. However, as to the occurrence of amitosis, binucleate 
cells, fusion nuclei with double the normal number of chromosomes 
and a heterotypic reducing division in the same, opinions are very 
conflicting. 
Grrasstmow (8, 9), NATHANSON (16, 17), PFEFFER (24), and 
WASIELEWSKI (30) found amitotic division of nuclei, but WISSELINGH 
(32, 33), NeEMEc (22), ANDREWS (2), and Woycickr (34) saw no 
cases of amitosis. 
Binucleate cells were observed by Grerasstmow (8, 9), NATHAN- 
SON (16, 17), PFEFFER (24), NEMEC (18, 20, 21, 22, 23), BLAZEK (3), 
WASIELEWSKI (30), Wovcickr (34), and STRASBURGER (29), but 
they were not found by WISSELINGH (31), ANDREWS (2), and 
KARPOFF (II). 
Fusion nuclei were reported by GERASSIMOW (8, 9), NEMEC 
(20, 21, 22, 23), who found also double the normal number of 
chromosomes, and by STRASBURGER (29), but not by the other authors 
mentioned. The disappearance of the nuclei with the double chromo- 
some number was explained by NEMEC (22) as due to a reduction 
division, in which he is followed by Woycrick1 (34). This conclusion 
is severely criticized by STRASBURGER (29) and by LarBaCH (12). 
From this brief statement of the conflicting opinions advanced 
in some of the more important papers dealing with the direct effect 
of various chemical substances upon nuclear and cell division, it 4 
evident that a much wider range of observation and experiment 1S 
required before conclusive generalizations can be drawn OF the 
discordant results of. the various investigators be brought into har- 
mony. Moreover, in the higher plants the rate and the amount 
of growth in the seedling stages have been used almost entirely m 
the measure of the toxic effect, or when such was not the case some 
microscopic’ factor has been employed. Apparently there has bees 
little detailed comparative study of the cell and nuclear activities In 
the higher plants during the course of treatment with an extended 
series of dilutions of a toxic agent. 
