Vlll PREFACE. 



synonyms of earlier species, and will have to sink. 

 Subsequently, the same author dealt with about fifty 

 species of British Coccidae, including several new 

 species, and the following new genera: /xr////^x///X 

 Gymnococcus, and Cryptococcm. 



As a practical gardener, I had for many years been 

 fully acquainted with the destructive habits of the 

 " mealy bugs " and " scale insects " of our fruits and 

 cultivated flowers; but it was not until the year 1889 

 (three years after my present appointment) that I 

 began in earnest the study of the group on more 

 scientific lines, when, acting under the advice of my 

 late employer and friend, Mr. Alfred Osten Walker, 

 F.L.S., I began a systematic study of the group. My 

 first reward was the discovery of the apterous ;m<l 

 winged males of Chionaspis xnfirix, Linn., \\liicli 

 discovery ultimately led to a lasting correspondence 

 with that able and accomplished entomologist, Mr. 

 J. W. Douglas, to whom I owe many debts of 

 gratitude for hints ungrudgingly given, and for the 

 liberal supply of all liis types, which, needless to 

 add, has very materially aided me in the preparation 

 of this monograph. 



All my contributions to the study of the Coccidae of 

 this country are given in tin 4 pages of the ' Ento- 

 mologist's Monthly Magazine ' (1891 to 1901), which 

 contains descriptions of about twenty new and unde- 

 scribed species, besides other interesting additions to 

 the British Fauna. 



At the present time about ninety species and varieties 

 of Coccids are known to occur in the British Isles ; of 

 which this volume deals only with the sub-family 

 Diaspinse. Of this comparatively small total those found 

 in our greenhouses and conservatories are undoubtedly 

 of foreign origin ; many of the indigenous species are 

 almost cosmopolitan; while a few, and especially the 

 subterranean species, may prove peculiar to the 

 British Isles. 



It may be safely said that no work on the Coccidae 



