38 2 Proceedings of the Royal Irish Academy. 



with limpets and sea-anemones ; and in their fissures were living, besides the 

 Obisium, some of the usual associates of this animal, viz., the blue Collembolan 

 Anurida maritima, the yellowish earabid-beetle Aepus, and the blackish 

 staphylinid Mwralymraa brevipeime. Of the Obisium itself were observed 

 numbers of adult and partly grown individuals moving freely on the inner 

 surfaces of the opened fissures ; and in addition to these there were several 

 females enclosed in their silken brood-nests and bearing the embryo-mass ; we 

 saw also one or two moulting-nests containing the cast-skin of the animal. 



Obisium inaritimum, already known on the shores of the bays of Kenmare, 

 Co. Kerry, and Bantry, Co. Cork, is likely to have an extended range on the 

 littoral zone of Ireland. Beyond, it is known in the Isle of Man, on the 

 western and south-western shores of Britain, in Jersey, and on the northern 

 and western shores of France. 



Obisium muscorum Leach. 



A common species among dead leaves, moss, under stones, etc., from sea- 

 level to the tops of our mountains, but evidently scarce on Clare Island. 

 One specimen was obtained, in the scrub of Portlea, by sifting dead-leaves 

 and debris of ferns ; and this was the only one seen on the island. On the 

 adjoining mainland the animal has occurred at Delphi, Co. Mayo (Halbert)' 

 and Leenane, Co. Galway (Halbert). 



Obisium muscorum is common and widely distributed in Ireland, being 

 already known in the counties of Antrim, Tyrone, Armagh, Down, Dublin, 

 Wicklow, Carlow, Cork, and Kerry, as well as in Mayo and Galway as above 

 noted. It is generally distributed in Britain ; and its range abroad extends 

 from north of the Polar Circle in Norway to the Mediterranean. 



CHTHONIIDAE. 



Chthonius tetrachelatus Preys. 



A species living under stones, etc., more especially in maritime and 

 mountainous districts, and sometimes in old gardens. On Clare Island a few 

 specimens were found, north of Kinnacorra, on a rough slope of drift ; they 

 were living here, in characteristic fashion, in cavities formed by fragments of 

 rock which were irregularly massed together and more or less sward-covered. 

 On the adjoining mainland the animal has oecimed at "Westport, Co. Mayo 

 i Pack-Beresford) . 



Chthonius tetrachelatus is probably widely distributed in Ireland, where it 

 is known in the counties of Antrim, Dublin, Cork, and Kerry, as well as in 

 Mayo : it is common in Britain, and ranges widely in Europe. 



