VOLUME XXI. 



THE AQUATIC COLEOPTERA OF THE 

 SOUTH-EAST OF IRELAND. 



BY FRANK BALFOUR BROWNE, M.A., F.R.S.E., F.Z.S. 



Out of some 220 species of water-beetles (Hydradepha 

 and Hydrophilidae, not including the genera Sphaeridium, 

 Cercyon, Megasternum and Cryptopleurum) recorded from 

 Great Britain, about 160 have, up to the present, been found 

 in Ireland. Messrs. Johnson and Halbert mention 138 species 

 in their list published in 1901,^ but from that list three 

 species recorded for the district covered by this paper should 

 almost certainly be removed, viz. : — Platamhus maculatus, L., 

 Ilyhius guttiger, Gyll.^ and Limnehius fapposus^ Muls. 



The lirst of these species was admitted to the list on 

 insufficient grounds, and, as it has not been taken since, I 

 think the name should be deleted. I have elsewhere ex- 

 pressed the opinion that it is a species which has compara- 

 tively recently spread to the west of Great Britain, its 

 absence from the Isle of Man and the western Isles of 

 Scotland, excepting Skye, supporting this view. From what 

 follows in this paper, if the species occurs in Ireland, I 

 should expect it to be found in the eastern or southern 

 counties, but at present there is no evidence that it exists 

 there. 



With regard to Ilyhius guttiger the species was first 

 recorded by Hogan ^ who stated that he took a specimen 



* A list of the Beetles of Ireland. Proc. Roy. Irish Acad., ser. iii., 



vol. vi. 



2 Catalogue of Coleoptera found in the Neighbourhood of Dublin. 

 Zoologist, xi., 1853, pp. 4 1 34-4 1 36. 



A 



