16,1 Haughwout and Youngberg: Trypanosomiasis 81 
Our previous experience with the so-called crithidial forms has 
been restricted to cultural trypanosomes and to species of Cri- 
thidia found in arthropod hosts. The picture of Trypanosoma 
rhodesiense as set forth by Stephens and Fantham(8) is already 
well known to men whose opportunities have made them much 
more familiar with trypanosomes than we are. It is our im- 
pression, however, that in the case of T. rhodesiense the posterior 
nucleated forms are more or less restricted to the short, stumpy 
trypanosomes that are found in subinoculated animals as rats, 
guinea pigs, dogs, mice, monkeys, rabbits, and horses, and are 
not seen in the human host. 
Inspection of our figures will show that the posterior-nucleated 
forms are by no means restricted to the shorter individuals, but 
are included among the longer trypanosomes often referred to 
as pre-division forms. Then, too, it must be remembered that 
our material was drawn direct from the original host. There 
is, of course, the bare possibility, which must not be overlooked, 
that our carabao may have become infected with trypanosomes 
drawn from the blood of the carabao from which the virulent 
rinderpest blood was obtained. 
In connection with their work on Trypanosoma lewisi, Min- 
chin and Fantham have shown the production of daughter 
trypanosomes from a parent rosette. These have a crithidial 
appearance, the parabasal lying anterior to the nucleus. But 
their figures show the nucleus lying in about the center of the 
cell, which is short and stumpy and quite different from the 
appearance presented by most of the trypanosomes on our slides. 
Furthermore, we failed to find any evidence whatever of soma- 
tella formation. 
It may be suggested that we are dealing with the “trans- 
vaaliense” type of Trypanosoma theileri. This may be true, but 
we can only say that, while not all the literature on T. theileri 
is available to us, inspection of the figures of Trypanosoma 
transvaaliense in Laveran’s paper ( 4 ) does not conduce to that 
belief. The impression given by Laveran’s figures is totally dif- 
ferent from that given by ours and the relative position of the 
nucleus and parabasal in T. transvaaliense seems to have been 
brought about by anterior migration of the parabasal. 
Macfie in his account of trypanosomes found infecting wild 
Glossina tachinoides(.&) figures Trypanosoma pecaudi (T. brucei 
of Uganda) from his rat No. 16 (see fig. 10, facing p. 438) with 
a pair of posteriorly situated nuclei near which is found the 
parabasal. This is in appearance somewhat similar to our 
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