MUS. 10S 



white. Palrns and soles naked, the former with five, the latter 

 with six pads, the last hind pad elongate. Pollex with a short 

 broad nail, all the other digits with claws : fifth digit on each 

 foot without claw, reaching just to the base of the fourth. Tail 

 about the length of the body without the head, slender, scaly, 

 the scales rather irregularly disposed, very small, averaging about 

 twenty to twenty-two to the centimetre, the whole tail very 

 thinly covered with fine white hairs ; its substance pale flesh 

 color above and below. Palate-ridges as in Hydromys, i.e. three 

 predental, the third notched in the centre, three interrupted inter- 

 dental ridges, and one uninterrupted posterior ridge. Mammae 

 0-2 = 4. Upper incisors long, less curved than in Mus ; their 

 front surfaces smooth, ungrooved, and orange in color : lower 

 incisors very long, their front surfaces white. 



Habitat. Port Mackay, Queensland. 



Dimensions. ? ad. Head and body about four and a half 

 inches ; tail about three and a half inches. 



References, Thomas, Proc. Zool. Soc. 1889, p. 247, pi. xxix. 

 ff. 1 4 (skull), 5 ( palate-ridges), 6 (anterior zygoma-root), 8 (ear), 

 9 (right hind foot), and 10 12 (left upper and lower molars). 



Subfamily II. MURING. 



Rats and Mice. 



Molars tuberculate, at least in youth. Cheek-pouches absent. 

 Tail scaly, more or less naked. 



This sub-family contains about two hundred and fifty species 

 belonging to eighteen well defined genera. 



Genus III. MUS, Linnceus (1766). 



Incisors narrow, not grooved : molars small, with three series 

 of cusps across each tooth. Incisive foramina long. Coronoid 

 process of lower jaw well developed. Eyes and ears large. Fur 

 soft, sometimes mixed with spines. Pollex with a short nail 

 instead of a claw. No cheek-pouches. Tail long, nearly naked, 

 with rings of overlapping scales. 



Distribution. Eastern Hemisphere, except Madagascar. 

 Dentition. I. , M. \ = 16. 



JL o 



Mammce. Varying from six to twenty. 



Habits. Terrestrial or seniiaquatic ; fossorial ; normally grani- 

 vorous, but under pressure of hunger, or when a semidomesticated 

 existence has been taken up such, for instance, as in the case of 

 the House Mouse, Mus musculus, and the Brown Rat, Mus 

 decumanus omnivorous. 



