parasites.' It wiJl be remembered that Dutton and Todd** were unable 
to adduce much information regardinj^ the animal reactions in the 
course of the natural cli.scasc of the (ianibia, except in horses. These 
correspond to what arc manifc.sted in 'baleri' as outlined by 
Cazalbou.' In experimental animals (lie results coincide: the disease 
is acutely fatal in rats, guinea-pigs and dogs, though Laveran has 
noticed some slight variations in the mouse, and in all animals, as in 
dimorphon and congolensc infections, splenic enlargement is common. 
One further point of difference might be cited ; in sheep and goats 
experimentally infected with 7 . pccaudi, the blood, though virulent 
on subinoculation, very rarely shows parasites; in T. dimorphon 
infection this is not usual. Wc ha\ c already referred to the variability 
of these animals under e.xperimcntation. 
The parasite which was obtained in the majority of cattle at 
Broken Hill corrcsjionded to the original de.scription given by Dutton 
and Todd of T. dimorp/nui, in .so far that all three forms, including 
that with a free flagclluni, were fuun'd, and the animal reactions were 
similar. Since the free flagellated and tlie small forms were not 
present simultaneously, it is improbable that we were dealing with 
T. pecaudi) and as T. congoiense does not appear to occur in a ‘long' 
form it may also be negatived. 
3- Group including 7 . nanum, T. vivax and T. casalboui. 
This grou]), constituted on the grounds of immunity enjoyed by 
the usual laboratory animals, presents difficulties in the way of sub- 
dnosion, as from the very nature of the parasites they are more 
ifficult of use in experimental observation, and hence less studied. 
. , ^ ^ t ree species, 7 . naHU 7 u takes priority; but, if w-e may 
> '^^1 limited amount of work that has been possible. 
1 IS clearly separable from the other two on account of its morpho- 
.0. to 
th^tf , ^”^ 1 ' conjunction with Balfour’s observations^ 
to siih^r rabbits and a dog were not infected are held 
appearances*^1 that the morphological 
but thoimh th 'tadpole’ form of T. dimorphon-. 
some at least^ inoculated animals be small, infection, in 
.m. 
to y susceptible, been employed. Further 
