H. B. P^ANTHAM AND A. PoRTER 
131 
mice. Unfortunately, these important remarks appear to have been 
overlooked and the surviving author has since changed his views. 
We have no doubt in our own minds, from the description given, that 
the flagellates seen in the Gambia were herpetomonads. However, the 
matter is so important that the original statement of Dutton and Todd 
is reprinted in full. 
“Flagellata in the Blood of a Mouse. 
At McCarthy Island we obtained a few house mice and some field 
mice (Spec, unknown). 
Fourteen of the former in all were examined, and in the blood of 
three flagellated protozoa were seen. Twenty field mice were examined, 
but none were found to be infected. The organism occurred infrequently 
in the blood of the mice infected, and we never saw more than one or 
two parasites in a fresh coverslip preparation. 
The organism was striking, in that it presented characteristics 
which differentiated it, at a glance, from a trypanosome. It consisted 
of a long oval-shaped body with blunt rounded ends, to one of which 
a very long flagellum was attached. At this end the body tapered 
slightly. A glance showed that the long flagellum, slightly longer 
than the body, was the chief organ of locomotion. It acted as a 
tractellum, and obviously dragged the body of the parasite after it. 
On encountering an obstruction the flagellum lashed out in all directions, 
hurled the red cells behind it, and often twisted round, so that its tip 
reached past the posterior end of the body. On these occasions, it 
was easy to examine the structure and measure the length of the 
parasite, as the body w'as perfectly quiescent. The protoplasm has a 
slightly granular appearance and in its substance, placed a little in 
front of the centre and towards the flagellated end, is a collection of 
refractile granules. About 5/x from the anterior end is seen a highly 
refractile spot from wdiich the flagellum takes origin. No suggestion 
of an undulatory membrane w^as seen. The length of the body in the 
living condition is 20-8/.1, and its greatest width 3-2p.. The body of 
the parasite sometimes assumes an ‘S’-shaped form, on account of 
external pressure or rapid changes of direction of movement, but no 
active contractions of the protoplasm were seen. 
Unfortunately, two mice sent home infected with this parasite 
died on the voyage, and in the films made from the mice while in Gambia, 
no specimens have been seen. A small rat inoculated from one of the 
