MAMMALS COLIiECTEU ON THE ORANGE RIVER. 497 



runs astride of the river about halfway between Kakamas 

 and Upington. Though previously considered to be entirely 

 diurnal, during the hot season at any rate they become most 

 active towards sunset, while several Avere caught in traps set 

 overnight. 



They creep rather than jump among the rocks, and did not 

 aj)pear to be particularly active. Their habit of filling up the 

 entrances of their hiding places between crevices with a network 

 of sticks resembles that of Rattus namaquensis, except that 

 l.'irger and stouter sticks of succulent plants are laigely used. 

 Petromys, like Thryonomys, is a most dilKcult animal to prepare, 

 the skin i)eing of the consistency of wet blotting-paper. It may 

 be noted that a large area of broken hilly country is often like a 

 forest in that small mammals are generally more numerous 

 among the outside hills and rocks, in the same way that there is 

 more life near the edge of a forest. A female examined contained 

 one young." 



29. Lepus saxatilis aurantii, subsp. n. 

 d.72, 73. $.74,118. Louisvale. 2600'. 



" Not at all confined to rocky country — plentiful around 

 cultivation." — G. 0. S. 



General characters of ordinary saxatilis, the ears not especially 

 lengthened as in the Namaqua subspecies megalotis. Colour 

 above, where unbleached, rather paler grey than in tvuQ saxatilis, 

 but bleaching in summer to a much greater extent, the dif- 

 ference in summer specimens of both very striking. Type with 

 its vinbleached hairs "light buff" tipped with black, its bleached 

 areas wholly dull sandy. Crown bleached dull brownish. Throat- 

 band pale greyish buflfy. 



Skull with very large bullae, markedly larger than in the longer- 

 eared viegalotis. 



Dimensions of the type, measured in the flesh : — 



Head and body .540 mm. ; tail 117 ; hind foot 126; ear 137. 



Skull : greatest length 101 ; condylo-incisive length 89 ; length 

 of bulla 14. 



Type. Old femaie. B.M. No. 23.5.9.173. Original number 

 118. Collected 23 November, 1922. 



"While December specimens of L. saxatilis from Central Cape 

 Colony are little paler or more bleached than winter ones, these 

 November examples are all strikingly paler than any specimens 

 of the group tha,t we have seen, whatever time of year they were 

 killed. Such patches of fresh fur as are present are also some- 

 what paler than occurs in true saxatilis. The ears of this form 

 are only of the same length as in true saxatilis, hot of the 

 extraordinary dimensions of those pf L. s. megalotis, while on the 

 other hand its bullre are larger than those of any others of 

 the group. . . ' 



