THE HISTORY OJb' THIS WORK. XI 



Advantage has been taken of a generous offer made 

 by Professor G. S. West to select from his drawings 

 any figures desired. Those which have been repro- 

 duced not only add to the attractiveness of the volume, 

 but are also of interest as illustrating points alluded to 

 in the text. Still more valuable for a future volume 

 will be the rest, for they include some very beautiful 

 coloured figures without which no more coloured plates 

 could in all probability have been given, as there are 

 none amongst Mr. Cash's own drawings. 



An explanation remains to be made. The text of 

 this volume so far as relates to the descriptions of the 

 genera and species and also the remarks which follow, 

 are as written by Mr. Cash, Avith the exception of 

 additions placed within brackets [thus], and verbal 

 alterations, including transpositions. A few localities 

 have been added from published records and his 

 own lists, the names of several species have been 

 changed as indicated, and some of the dimensions have 

 been revised when they did not coincide with those 

 derived from a measurement of the figures. For the 

 synonymy I am alone responsible, Mr. Cash's death 

 having occurred whilst it was in preparation and 

 therefore before it could be submitted to him, and 

 although great care has been taken in its compila- 

 tion, there will doubtless be found in it some cases of 

 erroneous identification of critical species. It is not 

 carried later than the year 1908. 



JOHN HOPKINSON. 



WEETWOOD, WATFORD, 



25th October, 1909. 



