PKEFACE. 



THIS work must be considered as a companion to 

 my ' British Oribatidas,' published by the Ray Society 

 as their volumes for 1883 and 1887, but it must not be 

 concluded from this that I am going to continue the 

 series so as to include the other families of Acarina. 

 Life is short and science is long ; the few years which 

 I may have before me would be utterly insufficient 

 for such a task. 



With the Tyroglyphidse, as with the Oribatidse, I 

 have been forced to rely almost entirely upon my 

 own collecting for the British species ; for there 

 practically are not any records to help me; a few 

 scattered notices of individual species, and that is all. 

 Therefore I cannot rely upon this book containing 

 every species which exists in Britain ; still, as the 

 number of known species from anywhere is small, 

 and as this book will be found to contain a large 

 proportion of them, I think that I may fairly hope 

 that the omissions from it are not numerous. Perhaps 

 I have the better ground for this hope, as the absence 

 of records of new British Oribatidse since the date 

 of my work on that group would appear as if tlw 

 collecting for it had been fairly exhaustive. 



