349 
since the Rhodesian trypanosome differs from T . gambiense more 
than, for instance, T. brucei does from T. evansi. Secondly-, there 
is the history, taken in connection with the fact that, so far as we 
know, T. gambiense is conveyed solely by Glossina palpalis , but 
even should it prove that Glossina palpalis exists in the districts 
through which W.A. travelled, then all the more probable is it 
that we are dealing with a new species of trypanosome. 
It seems to us, however, that it is difficult in the absence of 
further knowledge to discriminate with certainty between these 
views. Yet, on account of its peculiar morphological features, this 
Rhodesian trypanosome at least merits a distinct designation as 
T. gambiense rhodesiense , adopting the trinomial nomenclature. 
Our own view, however, is that we are dealing with a new species 
of human trypanosome for which we propose the name Trypanosoma 
rhodesiense. 
ANIMAL REACTIONS OF T. RHODESIENSE 
The following table has been compiled from the data obtained 
by Dr. Yorke. For full details his paper* should be consulted. 
Duration of life in days 
- - 
Animal 
Duration of life in days 
a 1111111 >t & 
T. rhodesiense 
T. gambiense 
7 . rhodesiense 
T. gambiense 
Monkey— 
Guinea-pig 
11 
39 
39 
4 1 
42 
120 A 
134 
M. rhesus 
» 
9 
11 
27 
91 
»» ••• 
H 
11 
1 ) 
52 
76 
160 
167 
C. callitbricus 
8 
108 
11 
11 
82 
1 ) 
10 
149 
Dog . 
9 
12 
64 
34 A 
C. ruber 
H 
— 
>1 
11 • 
11 
13 
i 3 
— 
Rabbit 
19 
60 
Goat . 
45 
46 
85 
150A 
11 
'9 
109 
11 
55 
— 
11 
26 
125 
11 
» 
11 ••• 
11 
26 
3 ° 
32 
140 
64A 
90A 
Donkey . 
11 
28 
54 
- 
11 
45 
150A 
Pony . 
38 
— 
11 
32 A 
Ncg- 
____ 
— signifies no experiment. A signifies still alive. 
* Annals Trop. Med. and Parasit., Vol. IV, No. 3, p- 3 ^ 7 - 
