1910.) Diseases of Domestic Aramals in. Uganda. 3 
Length.—The following table gives the length of this species as found in 
Uganda, in the ox, monkey, dog, guinea-pig, and rat. Only one trypanosome 
was found in the blood of the original Mabira ox. It measured 24 microns. 
In the monkey only 11 trypanosomes could be found. In all the others, 
20 trypanosomes have been drawn and measured. These were taken as 
they came, except that dividing forms were passed by. 
Table I—Measurements of Z'rypanosoma brucer, Uganda strain, 1909. 
In microns. : 
No. Da Method z | 
Date. of Animal. of ate of fixing and | 
expt. ‘ staining. Average | Maximum | Minimum | 
length. | length. length. : 
1909. 
Aug. 12} 1461 Ox Not known | Osmic acid and| 24°0 24 0 24 °O | 
Giemsa 
Sept. 30| 1627 | Monkey 26th is 7 24°8 | 30°0 19:0 | 
Aug. 26| 1479 Dog 41st . 26 °5 32-0 22-0 
» 80| 1479 K 45th ki * 22-0 29 -0 16 °0 
Sept. 30| 1479 ss 76th i i 23 °5 34-0 20:0 | 
Oct. 11} 1644 | Guinea-pig 33rd = eh 20127 34-0 153029) 
» 18| 1644 40th i 27-1 34-0 17-0 | 
Sept. 9| 1482 Rat 5th sf ih 24-7 30-0 21:0 | 
is | 1482 i 9th ‘ ie 23 °5 315 19:0. | 
PiniG)| 1648 is 8th i “ 19°6 21-0 isons 
| 23°6 | 84-0 | 15-0 | 
| 
It will be seen from the above table that Zrypanosoma brucei, Uganda 
strain, 1909, varies in length between 15 and 34 microns. Doubtless, 
individuals could be found slightly longer or shorter than this if they were 
hunted for. In Table I, as already mentioned, the 20 trypanosomes drawn 
are the first met with, except that dividing forms are left out, and this rule 
is adhered to throughout. 
The average length of the 172 trypanosomes dealt with in Table I is 
23°6 microns; but, as this does not give much information, the following 
table has been prepared. This represents by means of dots the length of 
each of 160 trypanosomes, in eight preparations of 20 each. Although 
Trypanosoma bruce, is described as a dimorphic species, it must not be 
supposed that there is any strict line of demarcation between the long and 
slender and short and stumpy forms. There are the intermediate forms. 
This table is also useful in showing at a glance the distribution of the 
various lengths. | 5 | 
VOL. LXXXII.—B. B 2 
