INTRODUCTION. 53 



The fossil Marsupial remains of South America, 

 it would appear, as well as those of Australia, ex- 

 hibit the same types of form as those which at 

 present inhabit those regions. Dr. Lund, in his 

 " Survey or Sketch of the extinct species of Mam- 

 malia, which inhabited the highlands of tropical 

 Brazil previously to the last Geological revolution,"* 

 observes, relating to the Marsupiata, " of this family 

 there is only a single existing genus in this district ; 

 it is, however, tolerably abundant in species. These 

 admit of two subdivisions according to their size ; 

 one comprising the larger species, which, both in 

 habits and magnitude, may be compared to our 

 martens and polecats ; the other, the smaller, that 

 scarcely exceed in size our mice and rats. I am 

 acquainted with two species in the first division, 

 Didelphys aurita,^ Pr. Max., and D. albiventer, 

 Lund. ; and three in the latter, D. murina, Linn., 

 D. brachyura. Pall., and D. pusilla, Desm. I find 

 fossil remains of species belonging to both these 

 divisions, which, for the present, I shall refer to two 

 species." These remains were discovered by Dr. 

 Lund, in certain caves " which occur in the calcare- 

 ous rocks that traverse in various directions the in- 

 terior highlands of Brazil." 



The following fossil remains were discovered by 



* This communication was addressed to, and is now pub- 

 lished by, the Society of Sciences at Copenhagen. I quote 

 from the Rev. W. Bilton's translation of this paper, published 

 in "the Magazine of Natural History," see vol. iv., p. 313. 



f Did. Azarcs of most authors. 



