REPORT OF TRAVELLING PATHOLOGIST AND PROTOZOOLOGIST 
159 
is dravsrn to this point because of the recently published account of a Le^icocytozoon of the 
grey hawk {Asturinnea vionogrammica) of the Congo, by Dutton, Todd and Tobey ; in their 
description it is evident these authors have been led astray by the appearance of the parasite 
in the stained films, which were not controlled by observations on the fresh blood. The Criticism of 
parasite is described as consisting of a periplast, an ectoplasm and endoplasm and nuclear bodies, 
while in connection with the nucleus there is described a complicated process of development icucocytozoon 
of a structure called the “line.” In one place it is said the host nucleus “has frequently 
been extruded, and gametoeytes without any included host-cell nucleus are not uncommon.” 
In another place “ when matured parasites become rounded preparatory to conjugation, 
the periplastic sheath (fig. 77) is thrown off, together with the effete host-cell nucleus (fig. 31) ”; 
and again the younger parasites are spherical—many figures indicate they are animboid, and 
the presence of forms in plasm indicate that they may pass from cell to cell. “ The younger 
parasites seem to apply themselves to (figs. 1, 4, 25) or to enter (figs. 13, 16) the host-cell. 
The larger parasites engulf them (fig. 26).” Such and other conclusions are made from the 
four stained films which these observers had at their disposal, and without any reference 
to the fresh blood, though some of the processes described are most involved and would 
require much more evidence to establish than can possibly be found in the limited material 
at their disposal. The great majority of the parasites figured in their plates are much 
deformed and distorted, for I have often seen such in badly prepared films from the blood of 
the guinea fowl. At another part of their paper {yage 323), and in reference to another parasite, 
the above-named observers say: “ We are fully aware of the necessity for caution in 
determining a developmental process from stained specimens,” yet they do not hesitate 
to describe a complicated change as the development of the “ line ” and other processes 
from such material. It seems as if these authors have been unduly influenced by the cycle 
of development described by Schaudinn in a similar parasite, with the result that they have 
attempted to fit in with his description the appearances in their preparations. Their remarks 
on the Leucocytozoon are qualified by a footnote which reads : “ The dangers of constructing a 
part of the life-history of a parasite from stained specimens alone are apparent,” yet they are 
able to follow the development of the “ line,” the extrusion of the host-cell nucleus, the 
preparation of the gametoeytes for conjugation, the amoeboid character of the young forms, 
and the wanderings of the young forms from cell to cell, and finally the fact that the young 
forms “ apply themselves to ” or “ enter the host-cell,” while the older parasites “ engulf 
them.” Looking at the last of these points alone, reference to the figures given illustrating 
the processes of cell infection will show that these are quite inadequate and unconvincing and 
do not represent the processes ascribed to them. This is all the more clear when one bears in 
mind that all the figures quoted are of greatly altered parasites, and I may state at once that 
examination of the fresh blood of the guinea fowl rarely shows any but the typical spindle 
structure with the drawn-out pointed ends, and that in stained films, especially such as have 
not been well prepared, as a result of slow drying or other cause, distorted parasites are 
constant, and these correspond in every way to the figures given in Plate XX. of the paper by 
Dutton, Todd and Tobey. The figures on the other three plates illustrating this parasite are of 
less deformed parasites, though still so much altered that it is unsafe to draw from them any 
important conclusions. The staining is not good, and, as is common with blood parasites, 
distorted and squashed forms often stain in a curiously abnormal manner. The three 
observers at the very outset commence with a wrong conception of the structure of the object 
with which they.wmrked. They have followed Schaudinn, who, we shall see, w'as quite wrong 
in his idea of the relations of the several parts of the parasite and host-cell. Descriptive 
names for the several parts have been given, and as these depend on their erroneous view as 
to the meaning of the different structures encountered, they will have to bo abandoned. 
