47 2 Proceedings of the Royal Irish Academy. 



of schistose reefs and boulders, changing to granite on Carrigeeninore. The 

 rocky shore alternates with stretches of clean sand or Zostera beds. On the 

 north side of Barranagh is a patch of muddy gravel. An extensive Laminaria 

 belt fringes the rocks at low-water, and the fauna which it shelters was very 

 thoroughly investigated. This varied littoral sheltered an exceedingly rich 

 fauna. A considerable amount of dredging was done in the adjacent waters 

 of the bay, but the sea-bottom is here very uniform, and the fauna is 

 comparatively poor in species. 



II. Clew Bay. — Geographically speaking, the western limits of Clew Bay 

 are formed by lines joining Clare Island to Achillbeg on the north and to 

 Boonagh Head on the south. Large collections, however, were accumulated 

 by dredging operations carried out in the area lying to the west of these lines, 

 for which there is no convenient name. For the purposes of this paper, 

 therefore, 1 propose to apply the name ' Clew Bay ' to the open water east of 

 a line joining Achill Head to Inishark. The eastern portion of this area, 

 comprising "Westport Bay and Xewport Bay, forms a separate faunistic area, 

 and is divided from Clew Bay by a line running from Mulranny Station to 

 Dillisk Bocks. Xone of the species listed in the ' Clew Bay ' sub-area were 

 obtained by shore-collecting. 



The sea-bottom of ' Clew Bay ' is predominantly sandy. To the north- 

 east and east of Clare Island lies a large area of trawling ground, having a 

 bottom of clean sand. In this area drifted Laminaria roots are frequently 

 taken in the trawl or dredge. To the north and north-west of Clare Island 

 the ground is rocky, with loose boulders, and yielded very few species. In 

 the area lying south of Clare Island and east of Inishbofin are many patches 

 of gravel and loose stones. This type of bottom yielded the largest number 

 of new or rare forms, and is characterized by a rich fauna of species of small 

 size. The characteristic species is Polygordius lacteus Schneider, and hence 

 this type of ground may be called for convenience " Folygordius ground." 

 Similar ground occurs to the south of the Curraun peninsula. Bound the 

 patches of " Polygordius ground " are extensive deposits of shelly sand, 

 which yield a very interesting micro-fauna, somewhat resembling that of 

 the " Polygordius ground." 



III. Clare Islam). — Shore-collecting for Polychaetes in Clew Bay was 

 confined to the shores of Clare Island, and was by no means exhaustive. 

 The north, south, and west shores are much exposed to storms, and yielded 

 practically no species of Polychaeta. The east shore is more sheltered, and 

 there are numerous rock-pools, loose boulders, and growths of Lithothamnion. 

 Xear the harbour is a patch of clean sand. 



IY. Newport Bay and "Westrort Bay. — For the purposes of this paper 



