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The urine is acid, contains haemoglobin (? methae- 
globin) red cells and, not uncommonly, casts and bile 
pigment. The tissues are more or less pallid, and 
there may be icterus more or less pronounced. 
The spleen is enlarged. The liver is enlarged 
and often fatty. The kidneys may be normal, or may 
in haemoglobinuric cases be greatly congested. In 
old standing cases they may shew few or no changes, 
or may be large and pale. The bone marrow is foetal 
in character. The urine may contain haemoglobin 
or be dark yellow in colour, but even in acute cases it 
is often clear and free from blood pigment. In 
chronic cases it is normal in appearance. 
Transmission. — H. leachi is a known carrier in 
Africa. Takes infection in adult stage, gives infection 
in subsequent adult stage. Eu. sanguineus , the 
most widely spread dog tick of the world, is a carrier 
in India. Takes infection in adult stage, gives infection 
in following nymphal and adult stage. 
Corresponding to this we have the following 
cycle of development :— 
Development in the Tick (Christophers).—(1) The 
parasite enlarges in the gut of the tick and becomes a 
motile club-shaped body, which then leaves the gut and 
penetrates an ovum becoming in the substance of this 
a ‘ zygote 5 ; (2) This zygote increases in size and breaks 
up into £ sporoblasts,’ which are found disseminated 
in the tissues of the larva ; (3) These sporoblasts 
further divide up and accumulate as £ sporozoits 5 in 
the salivary glands of the nymph ; (4) Sporozoits 
accumulate also in the salivary glands of the adult 
tick. They resemble the parasite in the blood except 
that they are much smaller. In infected ticks they 
are present in immense numbers (Plate III). 
Cultivation. —Prepare a number of test tubes 
u . 
