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XVI. British Species of the Genus Stenus. By Messrs. 

 G. R. Waterhouse and E. W. Janson. 



[Read 1st January, 1855] 



In the paper which we have now the honour of laying before the 

 meeting, we originally proposed to furnish a list of the British 

 species of the genus Stenus, as identified with the descriptions in 

 Erichson's " Genera et Species Slaplu/linorum," but subsequently 

 we thought it desirable to append to the last our determination of 

 the species of Stenus contained in the collection of the late Mr. 

 J. F. Stephens as well as in that of the Rev, VV. Kirby. 



To render the list as perfect as possible, we have been kindly 

 assisted by the loan of the entire collection of Stenidce of several 

 of our most assiduous Entomologists, and we have especially to 

 thank Messrs. Wollaston, J. Curtis, and S. Stevens for such 

 assistance. 



With regard to the Stephensian collection (now in the British 

 Museum), it is desirable to state, that the specimens which Mr. 

 Stephens used to call his " Type specimens"' are almost always 

 marked by some kind of ticket attached to the pin holding the 

 insect. The Marshamian specimens are thus marked by a round 

 yellow ticket; and when the species is described in the '■^Entomologia 

 Brilannica,'' a number will be found on the under side of the 

 ticket, corresponding to the number of the species in that work. 

 Other type specimens are either marked by a round white ticket 

 without a number, or by a small square ticket with a number. Mr. 

 Stephens' own species are not marked. The species follow in 

 succession, in the cabinet, in accordance with the descriptions in 

 the " Ilhistralions," but in one or two instances there have un- 

 doubtedly been some accidental transpositions ; and to prevent 

 further changes of this nature, all the species, and indeed nearly 

 all the specimens, have now been numbered to correspond with 

 the numbers of the species as given in the " Manual." The 

 numbers here alluded to are on small oval tickets attached to the 

 specimens, and it is to these numbered specimens that we more 

 particularly refer in the notes which are contained in this com- 

 munication. 

 The paper is divided into two parts : the first containing a list 



