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nucleus. These are shown in figs. 4 and 5. In fig. 4 there are two nuclei 
side by side, while there is a darker portion of the protoplasm which 
has somewhat the appearance of one of the “brown bodies” (BB). In 
the other individual (fig. 5) there are two nuclei side by side as in fig. 4 
but there is also an additional, elongate nucleus in this case. The brown 
body is much more clearly defined in this individual, is much darker 
and has more of the appearance of the body as seen in the living speci- 
mens. It has taken the stain rather deeply. 
I hesitate to draw any conclusions regarding the nuclear phenomena 
feeling that the stages fig. 4 and 5 represent only two phases of what is 
probably a relatively long series of changes. All of the observations 
are preliminary and may perhaps be continued if it is possible again to 
get material in this stage of development. 
State College, Pennsylvania, May 25st 1913. 
My dear Hedges: 
I have read your paper and studied your slides with much interest. 
Two points among your observations seem to me of especial interest — 
first, the great rapidity of the copulation process, and second, the fact 
that the gametes are of considerable size and do not, so far as I can 
determine from your slides, contain caryosomes in their nuclei. 
Copulation has been observed by a number of students in about a 
dozen different species of Amoeba. These are, however, all small forms 
with nuclei containing caryosomes. The large vegetative forms of 
Amoeba, like the common Amoeba proteus, have nuclei without caryo- 
somes, but these have never been found in copulation. The minute 
gametes of Amoeba proteus, whose copulation I have observed, have 
nuclei containing caryosomes. If you really have here gametes with 
nuclei which contain no caryosomes, and this appears to be the case, it 
is of much interest, for caryosome nuclei are almost unquestionably the 
more primitive, and gamete nuclei, not only in Amoeba proteus, but in 
general, show a somewhat primitive condition. If in your species even 
the gametes show the modified type of nucleus, the species is, in this 
important feature, the most aberrant Amoeba known. 
From your slides and description I cannot identify the species upon 
which you worked, nor is it likely that I could have identified the living 
individuals. Identification of species in this “genus” is often very diffi- 
cult. Different forms taken by individuals of the same species in corre- 
sponding and different stages of the life history have been given invalid 
specific names. Probably several species assume the lömax form, and 
it is doubtful if there is a distinct species which can properly be called 
A. imax. The same is true of A. radiosa, and several other forms. 
