228 
represented by the spherical parasites,. consisting almost entirely of 
nucleus, which result from the disintegration of trypanosomes 26, 
(3) There is reason to suspect that a sexual cycle may also 
occur; it may be in either or in both hosts. 
(4) The rapid spread of sleeping sickness cannot be fully explained 
by (1) alone; the cycles of development mentioned in (2) and (3) 
probably play a very important part in the transmission of the disease. 
Runcorn Research Laboratories 
April, 1907 
LITERATURE 
'• Dutton, J. E., and Todd, J. L. Memoir XI, Liverpool School of Tropic.il 
Medicine, Sept., 1903. 
■i. Bruce, Nabarro and Grf.tg. Reports of the Royal Society's Sleeping Sickness 
Commission, No. 4, p. 67-61, Nov., 1903. 
3- Kilborne and Smith shewed that the progeny of ticks fed on cattle inf 1,1 
with Piroplasma bovis of Texas fever were alone capable of transmitting 
the infection. 
4 - Thomas and Linton. The animal reactions ... of Trypanosoma gambunn 
Die Lancet, May 14, 1904. 
V Newstead, Dutton and Todd. Insects collected in the Congo t ree State 
Annals of Tropical Medicine and Parasitology, Vol. I, No. i, p- ^ l e 
>907 (Liverpool School of Tropical Medicine). . . 
‘ rTTOX and To »u- Memoir XVI, Liverpool School of Tropical Medicine. 
P a ge 97 . August, 1904. 
Di ITOK, Todd and Christy. Memoir XIII, Liverpool School of Tr0 P ua 
Medicine, page 97. 
Bruce, Nauarro and Grkig. 
'S' Na,!ARRo a " d Greig. U 
Commission, July, ^ 
RKiG. Report V of the Royal Society Sleeping 
Sickness 
