Some Observations on Amceba proteus. 201 
one, two, four, six, eight, and so on up to about seventy nuclei. Odd numbers 
of genuine nuclei are rare, and when present two nuclei will be smaller than 
the rest. 
REPRODUCTION. 
Descriptions of the processes of reproduction vary, probably owing to 
the “type” of the original material. 
To Awerinzew! is due the honour of being the first to describe mitotic 
division in the amceba he has called 4. proteus Pallas. He gave no drawing 
of the amceba, simply the nucleus in its different phases of mitosis; the 
paper is written in Russian, an appended note in German gives no text 
description, but on my inquiry Awerinzew? assured me that he found 
division by mitosis common. As my description and drawings of the 
mitotic division in the nucleus of the amceba, which I have also styled 
A. proteus Pallas, differ from his own he questions the accuracy of these 
illustrations, considering the cases to be similar. My drawings are accurate. 
I should, therefore, prefer to conclude that we were working on different 
“types” of A. proteus. He on A. proteus Y and I on A. proteus X, 
If this be so then the nucleus of A. proteus Y divides by mitosis and, 
from Stole’s* account, by amitosis also. Here again, in this case, there 
is no distinction between the types, but Dr Stole most courteously sent 
me all his papers on the subject and told me that he had worked on 
A, proteus as figured by Leidy. On reading his papers, I concluded that 
he had worked on A. proteus Y in these cases of direct division. His 
best paper with figures (1899) is written in his native language, the 
others in German. Unfortunately I have not been able to obtain a translation 
of the former since I received it, but the illustrations lead me to presume 
that he had observed both Y and Y; the details are not clear. 
With regard to A. proteus Z, the multinucleate form, it would appear 
to act as a plasmodium. Some authors mention having watched it nearly 
divide. I have been fortunate in obtaining division in three or four 
specimens. One particular case I watched during the whole night, and 
was finally rewarded by a division of this very large individual into 
two equal multinucleate daughter amcebe. Do these multinucleate products 
divide, or fragment still more, or may it be as already suggested by some, 
that the amceba proceeds to encyst in this condition? Of either of these 
processes | have as yet no absolute proof of my own, although many 
observations point to both being probable. 
1 Awerinzew, Zool. Anz., Bd. xxvii., ‘‘ Uber die Teilung bei Am«ba proteus,” 
* Awerinzew, loc. cit. 
? Stole, loc. cit., also Korenonoxci do Uttova slouniku nuuéného. 
