98 1 Jic Irish Naturalist. April, 



both .cjroiips. To do this it would be desirable to divide the island into 

 several districts, and the adjoining mainland likewise, and to compare the 

 fauna and flora of each. The question of the date of the final separation 

 of the island from the mainland was of course most important, and an 

 exact study of the flora and fauna would probal)ly throw much liolit on 

 this. 



C. U. ^lOTi'AT drew attention to the fact that in the fauna and flora of 

 the island. difl"crences might be expected to develop after insulation in 

 five principal directions: — i. A large number of animals and plants 

 would (from a variety of causes) die out on the island but survive on the 

 mainland. 2. New species might establish themselves on the mainland 

 but fail to reach the island. 3. Competition with these new species 

 might cau.se some of the old species to disappear on the mainland which 

 would still .survive on the i.sland. 4. The re-adjustment of the balance 

 of competition due to all these changes might cause some species which 

 inhabit both mainland and island to be much more numerous on one 

 than on the other. 5. Varieties! or in extreme cases new species) might 

 originate on either the island or the mainland without reaching the 

 other. 



J. N. IIai.rkRT referred to the lack of information concerning the 

 insect fauna of the larger islands off the west coast. Achill has been 

 only partially explored, but some interesting insects are known to exist 

 there, notably the excessively local moth Nyssia zoji'iiia : and a rare 

 alpine ground-beetle, Leis/its nionlauiis. was discovered a few years ago on 

 the summit of Slievemore. It was pointed out that the Rose-beetle, 

 Cefonia aura/a. a species of south-western range in Ireland, occurs in 

 abundance on the limestone tracts of Inishniore in Galway Bay. It was 

 considered likely that the entomology of Clare Island would yield some 

 interesting comparisons with that of the mainland. 



J. DF. W. IlrxcH suggested that the island was connected with the 

 mainland at the Glacial epoch, but that subsequently submergence 

 took place similar to that which occurred along the S.\\\ coast of 

 Kngland. 



J. Bayi^ev Buti,p:r stated that in the chart of Clew Bay the channel 

 between Achill and the island was much deeper than that between 

 Roonah Head and the island. He suggested that the land connexion 

 possibly existed for a later period between the two latter than between 

 Achill and the i.sland. 



Dr. PivTiiVBRiDCrK drew attention to the importance of investigating 

 the physiological characters of the alpine and southern plants which 

 grow side by .side in Clare Island and in the West of Ireland. The 

 conditions must be somewhat different to their native environment. 



IMarch 13. — KxciRSiON TO Zooi^ocrcAi, GARi)KXS.--Fifty members 

 and visitors assembled near the Superintendent's House at 2.30. The 

 party was then conducted through the Gardens, when Dr. Scharff" 

 pointed out features of interest. Tea was served at the Haughton 

 House. 



