RESEARCH IN BRITISH WEST AFRICA. Zo 
work it is better to boil in a mixture of equal parts of 90 per cent. alcohol 
(ordinary rectified spirit) and an aqueous solution (1 in 500) of perchloride of 
mereury. Even protozoal parasites are well preserved by this method. When 
fixed, preserve in 90 per cent. alcohol. Methylated spirit should not be used, as 
its acidity and other impurities may lead to embarrassment in the use of aniline 
stains, 
The corks of tubes containing alcohol should be covered with paraffin wax to 
prevent leakage. In hot climates the wax of a stearine candle will be found more 
satisfactory on account of its higher melting point. 
Collectors who desire to assist the Committee in furthering the organised 
study of African economic entomology should send their material to— 
The Scientific Secretary, 
Entomological Research Committee, 
British Museum (Natural History), 
Cromwell Road, London, S.W. 
IIl—INSTRUCTIONS FOR COLLECTING AND PRESERVING 
FLEAS. 
CoLLEctTINnG.—Fleas are found on both birds and mammals, but in order to 
secure them the hosts must be examined when alive or just freshly killed ; for 
fleas leave their host as soon as it gets cold. 
Should the host be small, immediately after death it may be placed in a cyanide 
bottle, or ina small box or tin containing a few drops of chloroform, benzine, or 
ammonia. The fleas, after a few minutes, will be found dead at the bottom of 
the receptacle or among the hairs and feathers. They can then be easily picked 
up with a small moistened paint-brush and transferred at once to the alcohol in 
the collecting tubes. 
In the case of large mammals and birds the fleas must be searched for by 
turning back the hair or feathers ; and they may be killed by touching them with 
a brush moistened with spirit, benzine, or chloroform. 
The following is a convenient plan for securing fleas found on birds :—Take 
a bird’s nest immediately the young have left it and place it in a box, preferably 
one lined with white paper and with a glass top. A certain number of fleas will 
probably emerge at once from it; but there will be many larvae and pupae still 
in the nest. These may be reared simply by slightly moistening the nest from 
time to time, and mature fleas will frequently keep on emerging for six or eight 
weeks after the nest has been taken. The live fleas can be taken off the sides 
and top of the box with a camel’s hair brush dipped in chloroform or benzine. 
If it is impracticable to breed the fleas in this manner, the nest may be shaken 
up in a linen or paper bag containing several drops of chloroform or ammonia. 
After a few minutes the contents should be spread out on a white cloth or paper, 
and the dead insects can be picked up with a moist brush. Nests of moles, 
rodents, &c., can be treated in the same way. 
