PROTOZOA IN BRITISH EAST AFRICA 
85 
Distribution. General in Africa. Morphologically iden- 
tical forms have been described from India, Australia, Japan, 
and Transcaucasia. 
Morphology. Occurs usually in the form of delicate rods 
and rings, the former measuring to 2^ in length, the latter 
lp to l*5yL6 in diameter. In appearance they are practically 
indistinguishable from Theileria parva, though a multiple 
invasion of a single red corpuscle is less common. No bodies 
resembling Koch’s bodies have been seen in connexion with 
this parasite. Bettencourt has placed this species in the genus 
Theileria, but it appears advisable to limit that generic name 
to those parasites which are non-inoculable by direct trans- 
ference of blood. 
Genus, Nuttallia. Franca. 
Species, Nuttallia equi. Laveran. 
Syn. Piroplasma equi. Laveran, 1901. 
Hosts. Horse, mule, donkey, zebra (P. H. Ross, Theiler). 
Distribution. Africa, including Madagascar, and India are 
the territories mainly affected, and it is known to be widely 
disseminated in East Africa. 
Morphology. The parasite is small, varying from 1^ to 
2*50 yu, in length and is frequently ovoid in shape. Twin pear- 
shaped forms comparable to Babesia bigemina or B. canis do 
not appear. It is not uncommon to meet with four or more 
individuals in a single corpuscle arranged as a cross or in a 
radial manner. 
Transmission. Theiler has shown that Bhipicephalus evertsi 
(the common red-legged tick) is the chief transmitting agent. 
Infection is acquired during the larval or nymphal stages, both 
of which are passed on one host, and is given by an ad alt to a 
second host. 
Pathogenesis. In general, Biliary Fever of Horses show's 
a similar train of symptoms to those of tick fever in cattle 
and in dogs, viz. fever and anaemia. The disease is readily 
inoculated by means of blood, and the parasite remains in 
the system of a recovered or ‘ salted ’ equine, and may there- 
fore cause a relapse. 
