110 MUS. 



Note. Dr. Ramsay is undecided as to whether this species 

 should be placed in the genus Mus or in Hapalotis (Conilurus 

 of this work). 



18. Mus ARGURUS, Thomas (1889). 



White-tailed Rat. 



Tail rather longer than the head and body. Ears rounded, 

 reaching just beyond the middle of the eye when laid forward. 

 General color above pale sandy-rufous, the hairs slate-colored 

 basally ; muzzle and underside of body white, the hairs of the 

 chest and belly rufous basally ; hands and feet pure white ; tail 

 wholly white, more thickly clothed than usual, the tip slightly 

 pencilled. 



Dimensions. Head and body to three and a third inches; tail 

 to four inches. 



Habitat. South Australia. 



Reference. Thomas, Ann. Nat. Hist. (6) iii. 1889, p. 433, fig. 

 p. 434 (upper -molar teeth). 



Note. As in the case of Dr. Ramsay's species just described, 

 Mr. Thomas was undecir'ed as to the exact position to which to 

 assign this curious form ; he remarks : " Mus argurus has the 

 external characters and the skull of Mus, with the molars of 

 Hapalotis ; and I am somewhat in doubt as to which of the two 

 it should be put into. It seems indeed probable that the charac- 

 ters of these two genera will be found so to blend together in the 

 different species as to necessitate their ultimate union, notwith- 

 standing the very striking characters presented by the more 

 typical species of Hapalotis." 



The following eight forms of Mus, which have been described 

 by Messrs. Higgins k Petterd from Tasmania, are here introduced 

 for the sake of comparison with southern continental species, as 

 it is impossible for the writer with the data, to hand to form an 

 opinion as to their validity or otherwise. It is not, however, at 

 all probable that the small island of Tasmania should possess no 

 less than eleven indigenous species of Mus, while but seventeen 

 have been described from Australia, one only being common to 

 both islands. 



19. MUS GRISEOC/ERULEUS, //. & P. (1882). 



Blue Rat. 



Ears naked and moderately long ; tail shorter than the head 

 and body, sparsely clothed ; fur long. General color above 

 bluish-gray, sides and below ashy-gray ; feet clothed with short 

 yellow hairs, tail with short stiff black hairs. 



