MAMMALIA. 



U:J 



24. MUS XANTHOPYGUS. 



Plate XXII. 



Mus xanthopygus, Waterh., Proceedings of the Zoological Society of London for February 1837, p- 28. 



31. supra pallidb brunneus flavo-lavatus, ad latera flavescens, subtiis alius ; capite gris- 

 cescente; natibus flavis ; pedibus albis ; auribus majusculis pilis,albis et flavis inter- 

 mixtis obsitis ; caudd quoad longitudinem, corpus fere cequante, supra, nigricante, 

 subtiis alba ; vellere longo et molli ; mystacibus perlongis albescentibus , ad basin 



Description. — Ears rather large, tail rather longer than the body, tarsi mode- 

 rately long and somewhat slender : fur long and very soft : prevailing tint pale 

 yellow; on the back there is a brownish hue owing to the long hairs, which 

 are thickly interspersed with ordinary fur, being of that colour: in the region 

 of the tail the hairs are of a rich yellow colour; the tip of the muzzle is white, 

 the feet, chin, throat and the whole under parts of the body are white ; on 

 the chest and belly a faint yellowish hue is observable : the tail is well 

 clothed with tolerably long hairs, those on the apical portion are the longer, 

 on the upper side of the tail they are of a brown colour, and on the under 

 side they are pure white : the ears are well clothed with tolerably long hairs, 

 those on the inner side are of a pale yellowish colour, externally on the fore 

 part they are brown, and on the hinder part they are yellowish white : the 

 hairs of the moustaches are numerous and very long; some of them are white, 

 but the greater portion are brownish black at the base and whitish at the 

 apex : the upper incisors are yellow, and the lower are yellow-white : the 

 hairs of the ordinary fur on the back are gray at the base, brownish at the 

 tip, and very pale yellow near the tip : the hairs on the belly are gray at the 

 base and white externally. 



Length from nose to root of tail 

 of tail 

 from nose to ear 



n. Lines. 



5 3 



3 10 



1 3 



Length of tarsus (claws included) 



of ear 



In. Lines. 

 1 1 



There are three specimens of the present species in Mr. Darwin's collection ; 

 two of them were caught when shedding their fur, and having lost the longer black 

 hairs, have the upper parts of the body of a paler colour; their general tint is very 

 pale, and may be described as gray, with a wash of pale yellow. 



