288 THE ANIMALS OF NEW ZEALAND 



Another interesting point with regard to the penguins is their 

 migrations, and the directions these have taken. New Zealand is 

 the only district in which both Megadyptes and Eudyptula live. 

 Formerly, it was the home of Palaeeudyptes. Therefore, it is 

 reasonable to assume that New Zealand was the centre from which 

 the birds dispersed. Some explanation of this is afforded by 

 geological evidence. During the Eocene Period the Andes had 

 not been formed, and the highlands of Tierra del Fuego were not 

 connected with the lands of the Northern Hemisphere ; and 

 South Africa seems to have been isolated from Northern Africa. 

 Therefore, Australasia was the only district where the land of 

 the Northern Hemisphere pushed down far into the Southern 

 Hemisphere. 



The next point that arises is in respect to the direction of 

 the migration from New Zealand. The species of Pygoscelis, 

 Aptenodytes, and the tufted penguin, being spread round the 

 Southern Ocean, do not help in a solution of this question. Had 

 the ancestors of Splieniscus passed from New Zealand westward 

 to South Africa, it would be reasonable to expect to find their 

 descendants on some of their immediate islands, such as St. Paul, 

 or the Crozets. This, however, is not the case. Therefore, it 

 seems to be more probable that they travelled eastward to South 

 America, w^here they arrived in INIiocene times, and thence to 

 South Africa. 



In the Southern Ocean the current runs from west to east, 

 and this would favour the spread of the birds towards the east. 

 It is evident that a penguin could swim across the Pacific Ocean 

 provided it could obtain food on the way, and Sir James Ross 

 saw some nearly 1200 miles from the nearest laud. It has been 

 supposed that in their migrations the.v have been much helped 

 by iceberg's, as penguins have )3een seen sitting on them. But 

 icebergs generality drift to the north, and could not supply the 

 birds with food. On the contrary, the melting ice would probably 

 destroy or drive away any fish or crustaceans in the neighbour- 

 hood. At first it is surprising to learn that SpJieiiisciis should 

 have spread so far north as the Galapagos Islands, but this is 

 easily explained when it is noted that the cold Antarctic current, 



