162 ALTERNATE GLACIAL PERIODS [Chap. XII. 



not exist in the low intervening hot countries. On the 

 Silla of Caraccas, the illustrious Humboldt long ago 

 found species belonging to genera characteristic of the 

 Cordillera, 



In Africa, several forms characteristic of Europe and 

 some few representatives of the flora of the Cape of 

 Good Hope occur on the mountains of Abyssinia. At 

 the Cape of Good Hope a very few European species, 

 believed not to have been introduced by man, and on 

 the mountains several representative European forms 

 are found, which have not been discovered in the 

 intertropical parts of Africa. Dr. Hooker has also 

 lately shown that several of the plants living on the 

 upper parts of the lofty island of Fernando Po and on 

 the neighbouring Cameroon mountains, in the Gulf of 

 Guinea, are closely related to those on the mountains 

 of Abyssinia, and likewise to those of temperate Europe. 

 It now also appears, as I hear from Dr. Hooker, 

 that some of these same temperate plants have been 

 discovered by the Eev. R. T. Lowe on the mountains of 

 the Cape Verde islands. This extension of the same 

 temperate forms, almost under the equator, across the 

 whole continent of Africa and to the mountains of the 

 Cape Verde archipelago, is one of the most astonishing 

 facts ever recorded in the distribution of plants. 



On the Himalaya, and on the isolated mountain- 

 ranges of the peninsula of India, on the heights of 

 Ceylon, and on the volcanic cones of Java, many plants 

 or, either identically the same or representing each 

 other, and at the same time representing plants of 

 Europe, not found in the intervening hot lowlands. 

 A list of the genera of plants collected on the loftier 

 peaks of Java, raises a picture of a collection made on 



