chap, xvn.] MAMMALIA. 249 



rat-like animal discovered by Mr. Fraser in Ecuador, and which 

 may perhaps belong to another family. 



Extinct Didelphyidce. — No less than seven species of Didelphys 

 have been found in the caves of Brazil, but none in the older 

 formations. In North America the living species only, has been 

 found in Post-Pliocene deposits. In Europe, however, many 

 species of small opossums, now classed as a distinct genus, Pera- 

 therium, have been found in various Tertiary deposits from the 

 Upper Miocene to the Upper Eocene. 



We have here a sufficient proof that the American Marsupials 

 have nothing to do with those of Australia, but were derived from 

 Europe, where their ancestors lived during a long series of ages. 



Family 77.— DASYUPtlD^E. (10 Genera, 30 Species.) 



General Distribution. 



The Dasyuridse, or native cats, are a group of carnivorous or 

 insectivorous marsupials, ranging from the size of a wolf to that 

 of a mouse. They are found all over Australia and Tasmania, 

 as well as in New Guinea and the adjacent Papuan islands. 

 Several new genera and species have recently been described by 

 Mr. G. Krefft, of the Sydney Museum, and are included in the 

 following enumeration. Phasgogale (3 sp.), New Guinea, West, 

 East, and South Australia; Antechinomys (1 sp.), Interior of 

 South Australia; Antechinus (12 sp.), Aru Islands, all Aus- 

 tralia, and Tasmania ; Chcetocercus (1 sp.), South Australia ; 

 Dactylopsila (1 sp.), Aru Islands and North Australia ; Poddbrus 

 (5 sp.), West, East, and South Australia, and Tasmania ; Myoictis 

 (1 sp.), Aru Islands ; Sarcopliihis (1 sp.), Tasmania ; Dasyurus (4 

 sp.), North, East, and South, Australia, and Tasmania ; Thyla- 

 cinus (1 sp.), Tasmania (Plate XL, vol. i. p. 439). 



Extinct species of Dasyurus and Thylacinus have been found 

 in the Post-Pliocene deposits of Australia. 



