Notes on a Neiv British Beetle. ^17 



the south of Dublin, in Counties Wicklow and Wexford. lyike 

 Helix pisa7ia, it occurs also in South Wales and South-western 

 England (North Devon). Now, most of the distinctive Celtic 

 animals of southern origin are characteristic of the west coast 

 of Ireland, where occur those plants of the Atlantic type 

 which have made our western counties so fascinating a field 

 for botanists. For example, the famous Kerry Slug, Geomalacus 

 viaculostis, and the Galway Burnet Moth, Zygcena nubigefia, are 

 unknown in eastern Ireland. It seems therefore that we can 

 trace for the Celtic animals of southern origin a western and 

 an eastern line of migration ; the former along the Atlantic 

 sea-coast of the old continental land, the latter along the 

 valley of the river which flowed south-westward from the 

 ancient St. George's lake, and which must have received the 

 Severn and the rivers of eastern and southern Ireland as 

 tributaries. Our fine Dublin House-Spider, Tegenaria hibernicay 

 Cb., very closely allied to a Pyrenean species, must be re- 

 garded as belonging to the eastern migration. It occurs in 

 Cork as well as in Dublin, but we must remember that the 

 Lee as well as the I^iffey was a tributary of the ancient eastern 

 river. This spider, though undoubtedly indigenous, has 

 apparently found human dwellings more comfortable than 

 the open air in our north-western island. 



If we accept Dr. ScharfPs view that our Celtic fauna is pre- 

 Glacial — and it is certain that it is older than the Teutonic 

 fauna — we might believe that by the ancient Atlantic coast, 

 and along the banks of this old river, such mild conditions of 

 climate prevailed that species were able to maintain them- 

 selves in those localities, while most of the present land-sur- 

 face of Ireland was covered with glaciers. The objection to 

 such a view, which will at once occur to geologists, is the 

 apparent submergence of the hills of Wales and Dublin to the 

 extent of about 1,400 feet as evidenced by the shell-gravel on 

 Moel Tryfaen and Two-rock Mountain. Moreover, the 

 marine origin of the Boulder-Clay which Mr. J. Wright's recent 

 discoveries of foraminifera in that deposit render highly 

 probable, would require a submergence as fatal to a pre-Glacial 

 fauna as the orthodox ice-sheet. But, if the migrations we 

 are discussing took place in Pleistocene times as the ice passed 

 away, and the land (after deep submergence and .subsequent 

 elevation) subsided towards its present level, the animals would 



