VI 
PREFACE. 
prevention, has been prepared by Prof. C. Y. Biley, the 
Entomologist of the United States of America. 
The appearance of this will leave little more to be de¬ 
sired—probably nothing more—regarding either history 
or means of j3revention; but when this paper was 
passing through the press my humbler effort w T as also 
prepared, and, as my promise had been given to publish 
it, I offer it accordingly. But I beg to draw the atten¬ 
tion of the reader to this not being an exhaustive 
treatise; it is intended merely to embody the notes of 
observation in South Africa, together with some simple 
principles of prevention, which however can be worked 
out fully only by residents who know the peculiar diffi¬ 
culties of weather, water-supply, &c., which have to 
be met. 
The notes of observation are valuable in many ways, 
and in my own part I have endeavoured, by great care 
and verification, to make up for my want of local know¬ 
ledge ; but with regard to the full history of the pest, 
and how to meet its ravages, I believe the best course 
for all who have to deal with it is to procure and 
practise the excellent information and advice contained 
in the paper on leery a purcliasi by Prof. C. V. Biley, 
Entomologist of the U.S.A., published in the Beport 
of the Commissioner of Agriculture, U.S.A., of the 
present year. 
The authorship of the various illustrations, of the 
notes of original and of published observation, are 
acknowledged as they occur; but I desire especially to 
mention, with many thanks, the assistance received 
from the skilled authority of M. Signoret, Paris, in 
determining the species of I. purcliasi, and likewise 
assistance from Mr. 0. E. Janson, London, relatively to 
