I. '08. 133 



Size. — The largest specimen examined measures 42 mm. 



General distribution. — P. varians is known from Sweden 

 (Goes), Denmark (Heller and Meinert), Friesland (Metzger), 

 Belgium (van Beneden), and France (Milne-Edwards). In 

 the Mediterranean and Adriatic it has been found in numerous 

 localities, including Lakes Garda and Trasimene in Italy and 

 L. Albafuera in Spain (Heller, etc.) ; it has been recorded from 

 Egypt (Heller) and is known in the Black Sea (Czerniavsky). 



This species is found rather commonly in suitable localities 

 on the south coast of England, extending northwards on the 

 east coast as far as Durham (Norman). I know of only one 

 record from the Scotch coast — Firth of Clyde (Henderson, 

 1886). 



Irish distribution. — Palaemonetes varians is probably not 

 uncommon in Ireland ; owing to its peculiar habitat it is doubt- 

 less often overlooked. It is known from the following locali- 

 ties : 



Co. Antrim. — Glynn (Eankin). 



Co. Down. — Belfast and Strangford Loughs (Bell on the 

 authority of Thompson). 



Co. Dublin. — In a slightly brackish pond at Sutton 

 (S.W.K.). " Pools on Merrion Strand " and at 

 Kingstown and Killiney (Kinahan). 



Co. Wicklow. — In a pond of almost fresh water close to 

 the sea at the mouth of the Vartry Eiver. 



Co. Wexford. — In ponds of almost fresh water close to 

 the sea at Courtown. 



In brackish ditches communicating with the 

 mouth of Wexford Harbour, near Eosslare 



(S.W.K.). 



Co. Cork. — In brackish ditches E. of Queenstown 

 (S.W.K.). 



Co. Kerry. — In ditches of almost fresh water at Darry- 

 nane (S.W.K.). Dingle and Ventry, "fresh- 

 water" (Dublin Museum). 



Co. Mayo. — Lough Learn and adjacent ditches, brackish 

 water (S.W.K.). 



In Ireland this species is generally found in pools or ditches 

 of almost fresh water, close to, but not directly communicating 

 with the sea. It is usually taken in company with Neomysis 

 vulgaris, on which it feeds freely, with the larvae of the dragon 

 fly, Ischnura elegans, and with various species of Khynchota, 

 chiefly of the genera Gerris and Corixa. It is only in the 

 southern part of its distribution that P. varians has been 

 found at any great distance from the coast line (as in L. Garda 

 and L. Trasimene). The species has never been recorded 

 from any of the Irish lakes, and it does not seem likely that it 

 occurs in them. 



