284 MAMMALS. 



received as indicating a continuance to the present day in Australia of the fauna which disappeared 

 in all the rest of the world with the close of the mesozoic period ; and this again carries with it the 

 belief that Australia was the most ancient coimtr_v in existence, having remained as dry land above 

 the level of the sea for a period corresponding to that in which all the mesozoic and cainozoic for- 

 mations of the rest of the world were being deposited. I am enabled to state that there is no 

 sufficient foundation for this theory, from the great quantity of fossils which I have lately examined 

 as Palasontologist to the Geological Survey of Victoria ; and from evidence of this kind I can offer a 

 sketch of the ancient successive changes of organic life in this coimtry."* 



He had fomid that the plants and animals in Australia have gone through exactly the 

 same phases as those of Em-ope, both before and subsequent to the oolitic period. First, the 

 palaeozoic plants and shells of Australia are proved by organic remains to have been formed on the 

 same tyqse as those of Britain. Next, at the oolitic period the whole facies of the fauna of the 

 sea and flora of the land had undergone just such changes as marked the geologically corresponding 

 creations in India, Yorkshire, Germany, and America. Lastly, in Australia, as in Em-ope, the 

 greater part of the comitry sank imder the sea during the tertiary period ; and every trace of the 

 previous creations of plants and animals was destroyed and replaced by a new set both of plants 

 and animals more nearly relating to those now occupj-iag the land and sea of the country, f And 

 these species were the antitjqjes of those now existing, — as the Dipkotodon of the Wombat, the 

 Macropus Atlas of the Kangaroos, and so on. 



Do these facts, separated from his inferences, bear out the conclusions arrived at by Professor 

 M'Coy ? Not in themselves, I think. He tells us that Australia during the oolitic period 

 had midergono changes similar to those which we know took place in Britain. I presume that no 

 marsupial remains have been fomid, or we should have heard of them. Professor M'Coy tells us that 

 no Trigonias have been foimd ; but the inference from the similarity spoken of by him is, that 

 they may be expected to have lived during that epoch : and if we may assume that, the position 

 of the inquiry then is, that as in Britain marsupial mammals then existed, so in Australia, or some 

 part of the southern hemisphere, they did so also. The whole of Australia was not afterwards sub- 

 merged : some parts of it were. Some parts of it did remain above water, and on them the ancient 

 marsupials may have lived, and their descendants developed new sj^ecies of the same type down to 

 the present time, each successive age gradually approximating them more to the existing species. 

 There seems nothing in the Professor's facts inconsistent with this, nor opposed to the old and 

 generally received belief. 



Notwithstanding his protest, therefore, I still regard the inhabitants of Australia as the least 

 changed descendants of the faunas of a tertiary or secondary age. I need not recapitulate the reasons 

 for believing in the existence of a continent or continents, in the South Pacific, at least as 

 old as Australia and Africa, and older than any other of our present continents. Nor need I argue 

 that the oldest laud is the place where the least changed forms of life are likely to be found, and 

 that the oldest forms are likely to be the least higlily organised ; nor will it bo necessary to do 

 more in order to show that the Marsupials ought to be so considered, than to hint at the e\'idencc8 

 of inferior organisation, shown by such reptilian characters as the permanent separation of the 

 bones of the skull, the imperfection of the palatine portion of the skull — the longer continuance 



• M'Coy, in " Annals of Natural History," 1SG2, p. 138. 

 + M'CoY, op. cit. p. 144. 



