23 12 Proceedings of the Royal Irish Academy. 



from their range in the country as known at present. So many old records 

 would have to be dealt with, however, that before one could accomplish this 

 work an almost complete re-survey of our whole island woidd be necessary in 

 the case of such species as Arwn hortensis, or of those just mentioned, all of 

 which live more or less under the " protection " of man. The bulk of our 

 molluscan fauna is, however, composed of " anthropophobes " rather than 

 " anthropophiles " ; thus when a re-survey of the country on scientific lines is 

 undertaken, the range of a species such as Hygromm fusca or Acanthinula 

 lamellata. may be taken as NNN, or at least NN*. 



The latter combination would have to be used where a plantation had 

 taken the place of a native wood, or where introduced trees, such as Fir or 

 Beech, are planted among native trees, thus altering the habitat from a 

 " natural " into an " artificial " one. For purposes of geographical distribution 

 only those species which can be conscientiously recorded as either NNN or 

 XX* are of the slightest use. Except around TVestport, Newport, Mulranny, 

 Louisburgh, and the smaller villages, by roadsides or in the neighbourhood of 

 habitations, man has not affected the mollusca of "West Mayo up to the 

 present. 1 



8. ANNOTATED LISTS. 



Claee Island. 



Perhaps nowhere in Europe is there a place in which the aboriginal fauna 

 can be studied better than in Clare Island. Man's influence is but little 

 noticed, as neither bis cultivation of certain portions of the island nor the 

 close cropping of other parts of it by sheep and cattle, appears to have 

 affected the mollusca to any extent. The reason for this is, I think, that 

 before the historic period the mollusks had been driven to the cliffs by the 

 heavy accumulation of peat on the flatter parts of the island. Here they 

 have dwelt secure, and are still unaffected by the changes that have taken 

 place in the other parts of the island. The partial draining of Lough Avullin 

 may have exterminated some fresh-water species, but no proof of this has 

 been obtained so far. The fresh-water fauna is, however, distinctly poor, and 

 I should have expected to find Planorbis glaber, Aplecta Kypivorvsm, and 



1 I have been forwarded by E. LI. Praeger four shells found in " mud from the boots of 

 Pat Grady on landing on Clare Island from Carrowniore, after two days at Louisburgh, November, 

 1910." The shells are four in number, two specimens being of Carychium minimum, and one each 

 belonging to Valfonia pulchella and Pupa anglica. All the shells had been dead for a considerable 

 period, and were perhaps wind-blown specimens derived from some of the coastal marshes near 

 Louisburgh. It is scarcely likely tbat living mollusks thus transported would found a colony, but if 

 nothing more the observation shows the danger of founding records of mollusca upon dead shells. 



