175 



colour ; the base of tlie liairs bluish- grey, with numerous 

 black hau's scattered throughout ; the fur gradually pales to 

 white on the entire under surface, where the hairs are 

 perfectly white to their base ; fore feet very pale fawn 

 colour ; hind feet white. In all other respects the female 

 resembles the male. 



Length from tip of nose to root of tail 8 inches. 



„ of tail 8 „ 



„ from nose to ear 1| „ 



to eye 1 ., 



„ of ear f „ 



Width „ f „ 



Length of fore foot and claws f „ 



„ hind foot and claws If „ 



skull If „ 



Width of „ I „ 



Length of nasal bones ^ „ 



„ lowerjaw 1^ „ 



Supraorbital ridge very prominent, extending as far back as 

 the occipital crest ; palatine openings long and narrow ; 

 coronoid process rather short and acuminate ; condyloid 

 process inclined backwards ; posterior angle rounded, nar- 

 row, and long ; descending ramus deeply emarginate. 

 Fig. 3. — Lower jaw, natural size. 



3a. — Superior molars magnified. 

 From Mr. Swan, of St. Leonards, to whom we are indebted 

 for the specimens, we learn that these rats are of many 

 colours. For this reason we have selected the specific name. 



MUS SiMSONI, 9. 



Ear moderately long, clothed internally and externally with 

 short brown hairs, which are rather darker on the outer 

 surface ; whiskers moderately long, dark-brown; fur greyish- 

 brown, interspersed with darker hairs ; under surface of a 

 paler tint ; face bluish- grey ; chin white ; fore and hind 

 feet clothed with short yellowish-white hairs ; tail moderately 

 clothed with pale-brown hair ; scales distinctly visible ; base 

 of tail thickened. 



Length from tip of nose to root of tail 2| inches. 



„ of tail 2| „ 



„ from nose to ear f „ 



to eye | „ 



„ of ear ^ „ 



Width „ A „ 



Length of fore foot and claws I „ 



„ hind foot and claws f ,, 



of skull I „ 



Width „ ^ „ 



Length of nasal bones J „ 



„ lower jaw ^ „ 



No supraorbital ridge ; condyloid process very convex ante- 



