337 
6. Examine from day to day, and make sub¬ 
cultures when a good growth is got (in about a week). 
Trypanosomes in cultures Tare generally small, 
5 to 15/^, but may be much larger, and they nearly 
always are of the Herpetomonas (p. 362) form. 
1. T. gambiense. —The cause of sleeping sickness 
or better human trypanosomiasis, a disease of tropical 
Africa. It is stated that native dogs (in Uganda) also 
harbour the parasite. 
Incubation Period. —Is not easy of determination, 
but can last months and probably years. 
Symptoms. —(1) A general polyadenitis, i.e., en¬ 
largement of the lymphatic glands, especially the 
cervical. (They may in some cases decrease again in size.) 
(2) Fever of an irregular remittent character, but 
frequently at first taking the form of an evening? rise 
followed by a fall in the morning. 
(3) Acceleration of the pulse and rate of breathing. 
(4) Skin lesions ; patches of erythema, e.g ., on 
the thorax, with congestion and some oedema giving a 
purplish appearance. A papulo-vesicular eruption is 
also common, especially in the native. 
(5) Oedema ; especially of the face, giving a puffy 
look, also on the legs and elsewhere. 
(6) . Nervous symptoms; first perceived, perhaps, as 
a mere alteration of expression or disposition. These 
eventually show themselves in headache, unsteady gait, 
tongue tremors, tremor of the outstretched hand, 
commencing apathy, disposition to sleep, lethargy, 
coma, death. Occasionally 6 sleep symptoms 5 are 
entirely absent. 
1. Blood Examination. —Parasites may be absent 
from the^ peripheral blood for a month or more at a 
time, and even if abundant, seventy to a cover-slip, 
may again completely disappear. The number of 
Y 
