283 



CHAPTER XL. 



MARSUPIALS. 



Marsupials. (Map 95.) I have been obliged to anticipate most of what I had to say regarding 

 the geological relations of the Marsupials. The reader knows that the oldest mammalian remains 

 yet met with have been found in the secondary rocks of England ; they are all insectivorous, 

 and they have, almost without exception, been proved to be marsupial. The oldest (Micro- 

 LESTEs) belongs to the trias, and it is marsupial. The next oldest ig from the oolite (Phasco- 

 lotherium), and it, too, is marsupial. Other marsupial remains have been found in the Purbeck 

 beds ; and it is more than doubtful if anything but marsupial animals have been discovered up 

 to the close of the secondary epoch. The doubt is not from contrary evidence, but from a deficiency 

 of complete evidence owing to the insufficiency of materials and the imperfect state of the bones 

 discovered. At any rate, the remains have sufficed to establish this, that if they are not Marsupial, 

 then they belong to the Insectivora.* The other orders do not begin, to show themselves until the 

 commencement of the eocene period. The marsupials were, therefore, so far as these records show, 

 the reigning, if not the sole, mammals in existence at the oolitic epoch. The nearest living relation 

 of any of them is the Myrmecobius of South-West Australia. The reader is also aware that such 

 tj^es of general structure of insectivorovis Marsupialia exist nowhere now on the face of the earth 

 except in Australia and South America, and that these remains have been found in the secondary 

 epoch accompanied by myriads of marine shells of the genus Trigonia, a genus not now existing in 

 any other than the Australian seas, where four species of it are not uncommon. The oolitic and 

 eocene flora of Europe has still more marked relations to the present flora of Australia. We 

 thence infer that at the close of the secondary epoch the fauna and flora of Europe extended to 

 Australia, where its type has remained to a certain extent unaltered, although it has been replaced 

 by another in Europe. 



There are no secondary rocks in Australia. There are palaeozoic and tertiary strata, but a gap 

 where the secondary rocks should be. It is, therefore, a natural, and, if our data are sufficiently 

 extended, a legitimate conclusion, that during the secondary period — viz. the period when Marsupials 

 appear to have been the sole mammals on the face of the earth — Australia existed as day land, and 

 that it was inhabited by the Marsupials then in existence. 



These conclusions have recently (1862) been challenged as imsound by Professor M'Coy of 

 Victoria. He says, referring to the class of facts above noticed, " Such facts are very commonly 



* "Tlie doubt when it has existed," says Professor also low in the class according to cerebral characters." — 

 Owen, " lies between this and the insectivorous order, Pahvontology, id. 407. 



