Migrator ij Birds uf Madeira and the Canaries. 161 



Peak of Teneriffe is visible at a distance out at sea though 

 obscured to those on the island. The same phenomenon takes 

 place in the other islands where the mountains are high. 

 During the months of July, August, and September, and also 

 occasionally during winter, no clouds appear on the mountains. 

 The botanical features of the islands are hardly what might 

 have been expected from their southerly position. A large 

 portion of the plants are either European or closely allied to 

 European species ; but there are others, such as the euphorbias 

 and laurels, widely differing from any thing now existing on 

 the neighbouring continent. The vegetation, especially of the 

 Canaries, may be divided into zones. Beginning from the sea- 

 shore, we get the remarkable Euphorbia canariensis (which, as 

 its name implies, is peculiar to this group), together with other 

 species of the same genus. A considerable portion of the land 

 has now been cleared and brought under cultivation, and pro- 

 duces cochineal, the chief export product of the islands. 

 At the height of about 3000 feet, or where the clouds caused 

 by the trade winds commence, the laurel forest begins, and ex- 

 tends upwards for some 3500 feet ; in this cloudy zone every- 

 thing is saturated with moisture, fostering the fine laurel 

 forest and grand ferns that abound there. Much of the forest 

 has now been destroyed by the improvident inhabitants for fuel 

 and other purposes; but the stumps of the old trees still indicate its 

 former extent. In some few places, where the cutting of trees has 

 been prohibited, one can form some idea, from the grandeur and 

 size of the til and laurel trees, of the character these forests once 

 possessed. Such are the forests of Tacaronte and Tagaiiana in 

 Teneriffe. Above the laurels, or at about 6000 feet above the sea, 

 comes a belt of tree heath [Erica arborea). This again is suc- 

 ceeded by a forest of pine trees [Pinus canai'iensis) , which towards 

 its upper margin become stunted. Finally, at about 9000 feet 

 there remains nothing but retama {Cytisus nubigenus), which 

 also is peculiar to these islands. Beyond the retama vegetation 

 ceases, and nothing but ashes and lava rocks remain, there being- 

 no trace, as on European mountain-tops, of any thing like an 

 alpine flora. 



These islands arc much frequented by Petrels and other 



