144 
KKI’OKT OF TKAVELLING PATHOLOGIST AND PKOTOZOOLOGIST 
T. lewisi in 
rats 
Trypanosomes 
of Nile fish 
Trypanosoma lewisi 
Plate X., tig. 15 
Trtipanosoma lewisi was met with in rats from various parts of the southern Sudan. These 
rats were all of the genus Mus. In one case inoculation of a small mouse (? young rat) from 
another rat infected with the trypanosomes of the donkey produced in three days an enormous 
infection of T. lewisi. In this animal all the reproductive forms characteristic of this trypano¬ 
some were found. In Plate X., tig. 15, is depicted a form which is interesting, as it shows very 
clearly the connection of the tiagellum with micronucleus. Each mioronucleus consists of 
two parts, a chromatic and an achromatic part. It appears as if the micronucleus is 
spherical, and the half of this sphere nearest the nucleus is chromatic, while the half directed 
away from it is achromatic. The whole micronucleus seems to be limited hy a delicate 
memiu-ane, which stains as the chromatic portion. The flagellum springs from the outer 
surface of the achromatic hemisphere and is directly connected with the membrane limiting 
the uiicronucleus. The tiagellum terminates at the surface of the micronucleus and cannot 
be traced into its interior. It would thus appear that the flagellum is in some way related to 
this limiting membrane. Possibly the same process which causes the formation of the 
membrane, if carried on actively at one spot, would result in a flagellum. In tig. 15 it will 
be noticed that connected with each micronucleus are two flagellum-like 25rocesses. One of 
these terminates at the surface of the l)ody; the other is prolonged as a free flagellum. 
Whether the shorter one is divided off from the longer or represents a new flagellum growing 
out from the mioronucleus cannot be stated. Laveran and Mesnil and MacNeal have described 
the connection of the flagellum of T. lewisi with an achromatic structure which lies close to the 
micronucleus. In the jn’esent instance the achromatic structure is jiart of the micronucleus 
and reminds one of the similar body seen in cultural forms of the jjarasite of kala-azar. 
Trypanosomes in Fish 
Trypanosomes were met with in several fish from the Nile. In the Farfou fish {Tilapia 
zillii) they were constantly present. The measurements of one of these trypanosomes was as 
follows : Non-flagellar end to micronucleus P5p, micronucleus to nucleus 13/i, length of 
nucleus 3p, nucleus to flagellar end 21/(, flagellum 14/i, width of body at nucleus 4p. 
Trypanosomes were foimd in the Bagara tish, Gargur fish, Noke fish as described by 
Sheffield Neave. I failed to find trypanosomes in Polypterus. There are several species of 
Gargur fish (llynodontis) in the 
Nile and each is infected with try¬ 
panosomes. I found tryjjanosomes 
in the Garmoot fish {Glarias anguil- 
laris) rarely, though this is a mud¬ 
feeding fish which abounds in the 
Nile, and esjaecially in Lake Ambadi 
on the Bahr-El-Ghazal. Trypano¬ 
somes were also seen in Ghrysich- 
thys auratii, and finally in the 
curious fish Ophioeephalus ohscu- 
rus a trypanosome and a hsemo- 
gregarine were found (Fig. 40, 
A and B). This trypanosome 
measures 40;i< in length and 3-4;i in breadth. The flagellum is about long ; mere is a 
large micronucleus situated at the extreme end of the] body, while the nucleus is behind the 
middle point of the body. 
