1920.] Birds of the Canary Islands. 529 



immense lava flows, miles ol: volcanic soil, cliffs of l)asalt, 

 tuff and volcanic debris meet tlie eye on all sides as one 

 travels through almost any island in the group. To remind 

 us that the Canaries are still the centre of a great volcanic 

 zone we need only go back as far as 1909, vvlien a small 

 eruption took place on the Peak of Tenerife (Geog. Journ. 



vol. XXXV.). 



Geologists have therefore concluded that the Canary 

 Islands were built uj) from the ocean bed by volcanic action ; 

 the recent volcanoes have been shown by von Buch and 

 others to be seated on a foundation of older rocks. 



The theory that the islands were once joined to the main- 

 land is considered by Lyell and others to he impossible — no 

 change in the ocean bed having taken place since the islands 

 were formed. The fauna of the Canaries also strongly refutes 

 those who believe that the Archipelago was once connected 

 with the mainland. 



As to the islands being the remaining peaks of a sunken 

 Atlantis there is no evidence Avhatever to support this view. 

 In fact there are many signs that elevation has taken place, 

 and no evidence of subsidence. As recently as 1912 the 

 legend of Atlantis was strikingly revived in Paris by a 

 distinjiuished Krench geologist, but a careftd |)eiusal of his 

 pajjcr '^■j though extremely interesting, has done little to 

 onvince me of its truth. 



Although varying views are held as to how the islands 

 were foi-medj there seems to be general accord as to the 

 geological age of the Archipelago — and all agree that the 

 Canaries were probably formed in the Miocene Epoch. 

 Possiliferous remains in Gran ('anaria have been discovered 

 which tend to prove that the island was thrown up from the 

 floor of the ocean in that [)art of the Middle Tertiary Age 

 known as the Upper Miottene. In the north-east of this 

 same island lies an immense marine terrace of mighty 

 marine conglomerates imbedded in which are calcareous 

 layers of Miocene date. 



In thus dating the birth of the islands it is interesting to 



* Smillisoniau lust. Aimual Keport, 1915, p. 222. 



