68 "^h^ Irish Naturalist. [ March, 



the present Irish area ; thence a limestone plain stretched 

 west and north-west as far as the present loo-fathom line of 

 the Atlantic. Established in this plain the colony invaded 

 our present Ireland from the west. And so we have around 

 Galway, Limerick, and Cork these animals, which are un- 

 known near Dublin, where we might rather expect to find 

 them. The Aran Isles are the remnants of the former ex- 

 tension of the limestone plain, and preserve for us some 

 survivors of this colony which made so gallant an invasion of 

 the far west. 



I must, in conclusion, ask your pardon for having put before 

 you at such length these tentative speculations. If they have 

 done anything to indicate the great questions which lie behind 

 the work of the humblest field naturalist, I shall be satisfied. 

 We doubtless all recall the noble passage at the close of the 

 ** Origin of Species," in which Darwin dwells on the intense 

 interest of some bank, covered with tangled vegetation, peopled 

 with singing birds, hovering insects, and crawling worms, in 

 the light of the descent of all these from " the few forms or one 

 into which life was first breathed." I^ooking back to a past, 

 distant though less remote, we may regard our animals and 

 plants as travellers which at different times and by various 

 roads have come to the spot where we now find them ; as 

 members of armies whose battles for the possession of our fair 

 land have been fought through ages, compared with whose 

 length the duration of the struggle of Teuton with Celt has 

 been but as a da3\ 



