Vi PREFACE. 
In some cases, of course, infestation can only be got rid of by 
measures specially directed to clear away the special trouble; 
but for the most part it is the large proportion of common farm 
measures which may be brought to bear on common farm pests 
(if only what is wanted is known to the agriculturist) of which 
the details are the most valuable for distribution. 
In submitting this my 13th Eeport firstly to those by whose 
observations most of the information contained in its pages has 
been contributed, I beg to offer my most hearty thanks for their 
assistance, including in this some of almost all the different 
branches of our great agricultural body, whether interested in 
crop or stock; and especially (for the investigation was for 
myself a most difficult task) the many who kindly aided me in 
the Warble investigation, and are still giving their influence most 
serviceably in the work of stamping out this most unnecessary pest. 
I have also to offer my best thanks to the Agricultural and 
general Press for the courtesy with which they give such efficient 
aid as could be gained in no other way, to my endeavours to be 
of some service in insect prevention. 
Beyond this country my thanks are also due to many corre¬ 
spondents, and especially to Mr. J. Fletcher, Dominion Entomo¬ 
logist, of Canada, for frequent and valuable co-operation most 
cordially given, and similarly to Mr. Frazer S. Crawford, 
Government Inspector under the Yine, Fruit, and Vegetables 
Protection Act, Adelaide, S. Australia; and to Mr. Albert 
Molineux, Sec. of Bureau of Agriculture, S. Australia. 
I am also indebted for much useful communication to Prof. 
C. Y. Riley, the eminent Entomologist of the Department of 
Agriculture, U.S.A.; and to Dr. J. A. Lintner, Entomologist of 
New York State, I am also indebted for courteous and valuable 
communication. Amongst European correspondents I must 
especially record my obligation to Dr. J. Ritzema Bos, Professor 
at the State Agricultural College, Wageningen, Netherlands, 
for his constant skilled co-operation, especially regarding the 
important and difficult subject of Nematode investigation, by 
which he has given us much very practical benefit regarding 
prevention of damage from Eel worms. 
Besides the benefit of correspondence, I am also under 
obligation for donations of many valuable publications sent me 
