108 SPECTES or GALAXTAS FOUND IX THE AUSTEALIAT^" ALPS, 



isolation of the group, there seemingly being no relationship with 

 any other family of fishes, unless the remarkable Mud Fish of 

 New Zealand [NeochanncC) forms an exception. The species are 

 numerous, but so much alike, that it is, looking at their distribu- 

 tion, more than probable that they are one and all only per- 

 manent local varieties of the same fish. 



But the chief interest attached to these fishes is in their 

 distribution. They are found only in the rivers of Southern 

 Chili, Magellan Straits, the Falkland Islands, Tasmania, New 

 Zealand, and those parts of Australia where the rivers take 

 their rise in the Snowy Mountains or in cold elevated table lands. 

 So that in fact we find this singular fish in all the lands which 

 extend into the colder regions of the Southern Pacific and 

 nowhere else. The deduction from this singular fact is very 

 plain. At one period, — probabl}^ very remote even in a geological 

 sense, — the area of land above the sea in the antarctic regions 

 must have been very much in excess of what it is at present, at 

 all events sufficiently extended to admit of some kind of 

 continuity across the whole width of the Pacific between the 

 southern extremity of South America and Australia. There is 

 no other way of accounting for the appearance of these fishes in 

 such widely difiterent localities. 



There are other instances of similarity in the Fauna of South 

 America and Australia, and Professor Hutton several years ago 

 in an essay, '' On the Geographical relations of the New Zealand 

 Fauna," (N. Z. Instit. Trans., vol. 5.) showed from the distribu- 

 tion of the Struthious birds in the Southern Hemisphere that 

 there must formerly have existed a huge Antarctic Continent, 

 connecting South America, South Africa and Australia. What 

 has become of this gigantic continent ? The Geologist's answer 

 will of course be that it has sunk, and such a theory is a most 

 convenient one, as it at once gets rid of all troublesome questions 

 as to the How and the Why. I think it however, more likely and 



