342 
A Critical Review, etc. 
Edentate, the two-toed sloth, Cholaepus diclactylus (Linn.) in St 
Laurent du Maroni. The parasite measures from 8—11 /x in length and 
from 2'5—4 p. in breadth, it is rounded at one end and pointed at the 
other, it is not pigmented. When stained by Giemsa’s stain it is seen 
to contain a circular nucleus and a well defined rod-shaped blepharoplast 
either lying beside the nucleus, anterior or posterior to it. The pointed 
end is described as the anterior and although in some of the parasites 
it is filamentous no flagellum could be demonstrated. The invaded 
corpuscles are not hypertrophied, nor do they contain any granules; 
they are simply deformed owing to the shape of the parasite. In the 
majority of the corpuscles only one parasite was found but in one there 
were two. Two elongated bodies, possibly parasites, were seen in a 
mononuclear leucocyte. 
The authors remark that this intracellular parasite recalls the 
Haeviocytozoa, for example the haemogregarines, in that it invades a red 
blood corpuscle, is elongated and not pigmented. They consider it 
constitutes an intermediate type between the Trypanosomata and the 
Haemocytozoa, like Leishmania, since it shows in the blood of a vertebrate 
host all the morphological characters of a true flagellate as Leishmania 
shows in cultures (sic) and in Cimex rotundatus. Mesnil and Brimont 
believe that this new parasite is more closely related to Trypanosoma 
than to Leishmania, and, as it invades the red blood corpuscles of a 
vertebrate, they have created for it a new genus, Endotrypanum. 
From an examination of the authors’ figures of the stained specimens 
it is clear that the parasite does not possess a flagellum; it therefore 
cannot have all the morphological characters of Herpetomonas donovani 
as seen in cultures and in Cimex rotundatus-, I have clearly shown that 
the parasite of Kala Azar is a Herpetomonas and not a Haemocytozoon. 
It is however certain that the parasite of the sloth represents a stage in 
the life-cycle of a flagellate, probably a part of th e post flagellate stage. 
The question naturally arises, how does it invade the red blood 
corpuscles ? The shape of the parasite certainly suggests that it may 
penetrate them when possessing a flagellum which later disappears. 
No free forms, similar to those in the corpuscles, were seen. It is possible 
this intraglobular stage is a transitory one and that the parasite 
undergoes other changes in the organs of the sloth. The rounded 
binucleate stage should certainly be searched for in the leucocytes and 
endothelial cells as well as in the transmitting invertebrate. 
The structure of this organism suggests that it is closely allied to 
the Crithidia as defined above. These flagellates have so far only been 
