^°'- "•! HUTTON, Pe/ipuins. K 



1902 J ^ &> ' J 



and throat. I infer this last to have been the case because in 

 Eudyptula the young in the down has the head and neck brown, 

 and it remains brown throughout life in all the species of 

 Spheniscus. It is probably the same in Megadyptes, for in 

 young birds the feathers on the throat are brown, like those of 

 the head. In CatarrJiactes sch/egeli, also, the chin and throat are 

 brownish in the young. In all these cases, except SpJieniscus, 

 the chin and throat subsequently become white, which I there- 

 fore suppose to be a later acquisition. 



In the other species of CatarrJiactes the young birds in the 

 down have the throat black ; then, with the first feathers, it gets 

 grey or nearly white, and then black again. Also the species of 

 Pygoscelis have the chin and throat white when young but 

 black when old. From all this we may infer that the black 

 throat in these species is due to atavism, and that their imme- 

 diate ancestors had white throats when adult. We may therefore 

 suppose that C. schlegeli represents the earliest species of the 

 genus, from which the others have descended, and we may 

 further suppose that C. clirysocome has been developed from 

 C. pachyr/iynchus, because the plumes on the head are so much 

 longer ; so that we have M. antipodus, C. sc/deg^/^, C. pachyrJiyn- 

 chits, and C. chiysocouie as the probable line of descent. 



Now let us see if we can trace out the migrations of any of 

 the Penguins. The fact that New Zealand is the only district 

 in which both Megadyptes and Eudyptida live, as well as its 

 being the former home of Palceeiidyptes^ point to New Zealand 

 as the centre of dispersion. Geological evidence helps to 

 explain this, for during the eocene period the Andes had not 

 been formed, so that the high lands of Tierra del Fuego were not 

 connected with the lands of the northern hemisphere. Also 

 South Africa appears to have been isolated from Northern 

 Africa, so that Australasia was the only district where the land 

 of the northern hemisphere pushed down far into the southern 

 hemisphere. 



Next, as to the direction of the migration from New 

 Zealand. The species of Pygoscelis, Aptenodytes, and C. cJiryso- 

 cotne, being spread round the Southern Ocean, give us no 

 help in this matter ; but if the ancestors of Spheniscus had 

 passed from New Zealand westward to South Africa we should 

 expect to find their descendants on some of the intermediate 

 islands, such as St. Paul or the Crozets, which we do not. So 

 it seems more probable that they travelled eastwards to South 

 America, where they arrived in miocene 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 



