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in an African village. Instruct him to muster the 
children of the village. The free display of £ pice/ 
half-pence, etc., will greatly aid one, and by palpating 
a few spleens previously to taking blood specimens 
the children will come readily. It is well first to take 
the blood of one or two adults or big boys so as to 
allay fears. In all cases it will be found best to take 
for granted the willingness of the child, and if the 
operation is quickly and quietly performed there is 
little objection, especially when each receives payment. 
Make twenty to thirty dried films or more. 
At the same time a spleen census may with 
advantage be made. 
On examining the films determine :— 
(i) Number shewing parasites or pigmented 
leucocytes in the blood. 
(ii) The species of each parasite present and 
the percentage value for each if the numbers are 
large enough. 
To Determine the Infection in the Anophelines 
(The Sporozoit Rate) 
1. Collect as large a number of Anophelines as 
convenient from the village in and around which 
the previous observations have been made. 
2. Dissect as many specimens as possible, noting 
in each case the species dissected, and noting in which 
species, if any, sporozoits are found. 
In many cases the sporozoit rate is extraordinarily 
low, e.g . 9 two per cent., although Anophelines are 
abundant and the malarial index is not low. In others, 
especially in African bush stations, the percentage 
may reach fifty per cent. 
3. Leave specimens not dissected, for several 
days, and examine the mid-gut for zygotes. 
