+ ot no i me) a 
abit 
j 922 
stool. The reasons governing the inclusion of red blood corpuscles by 
amcebex will be discussed in the chapter devoted to the pathogenic char- 
acter of the parasites. 
Bodies which appear like spores may often be seen in the endoplasm 
of adult amcebe and in the resting and encysted forms. At times, the 
arrangement and general appearance of the bodies strongly suggest their 
being spores, which they probably are, but at other times the picture is 
not so clear. Whatever the nature of these bodies, they apparently have 
to do with reproduction, but as we have not been able to follow Schau- 
dinn’s observations, nor to establish definitely their course and action, 
we do not desire to discuss the subject further at this time. 
(d) Nucleus—A nucleus is probably present in all amcebe, but in 
some it is difficult to see it and in others impossible to do so, and further, 
in the case of amoeba, it may at one time easily be observed and at another 
not found. It may be spherical, oval, vesicular or irregular in outline; 
located centrally or excentrically in the parasite; it varies considerably 
in size and in the amount of contained chromatin. A nuclear membrane 
may be very distinct or barely visible and there may or may not be a 
visible nucleolus. 
It will be remembered that one of Schaudinn’s strongest points of dif- 
ferentiation between “H. coli” and “H. hystolytica’”’ (except the distinc- 
tions based upon the modes of reproduction) was founded on observations 
upon the nucleus. In “2. histolytica” the location was always eccentric, 
the shape round, of small size or not visible, the chromatin small in 
amount and the nuclear membrane indistinct. In “ZH. coli” the picture 
was almost the complete opposite. 
These observations are not altogether true when pure cultures of a 
single species of amcebe are considered. The variation in the characters 
mentioned in such pure cultures is sufficiently great to make at least 
their diagnostic importance questionable. That Schaudinn’s conclusions 
are not always true in regard to amcebe in sections from lesions in the 
bowel and liver may be amply observed by any one sufficiently interested 
to study such sections. 
In summarizing this mass of fact and theory concerning the biology of 
amoobe, it is readily seen how difficult it is to systematize the points in 
such a way as to justify classification. We have failed to follow Schau- 
dinn or others in their species determinations, and it appears that many 
important premises upon which their conclusions were based are not 
borne out by our work. It seems to us that nfore work must be done 
before a satisfactory classification of these protozoa can be made, and 
until such a time we prefer and believe that we are fully justified in 
retaining the name Ameba coli Lésch, to represent those amcebxe which are 
found in the intestines of human beings. 
The bearing these observations have upon the pathogenicity of amcebe 
will be more fully discussed in the appropriate part of this paper. 
