PREFACE. 



The object of this Nomenclature is to present a Catalogue 

 of the well -established species of the Group of Coleoptera 

 called Hydrocanthari, with a reference to where they are fi- 

 gured, and to a few of the more important synonyma. 



It is intended for the following purposes : 



1. As a list of the species contained in the Museum 



Collection, with an indication of their origin. 



2. To point out the desiderata of that Collection at 



the period of publication. 



3. As labels for the cabinet. 



This list must only be considered as prefatory to a more 

 complete Catalogue. 



The Groupe, Hydrocanthari, is chiefly arranged after the 

 method of Dr. Aube, in his ' Species general des Hydrocan- 

 thares et Gyriniens,' with the additions and corrections which 

 have appeared necessary in the preparation of the list. 



Mr. Adam White has taken every care in the determina- 

 tion of the synonyma and figures ; and Dr. Schaum, of Stet- 

 tin, who has made the Groupe the particular object of his 

 study, has most kindly lent his very valuable assistance in 

 its preparation, and in the determination of the species and 

 the correcting of the synonyma. 



JOHN EDWARD GRAY. 



British Museum, 

 Nov. 1847. 



