368 Mr. O. Thomas on 



zygomatic breadth 31*3 ; breadth of muzzle above i 3 8*8 ; 

 nasals 205 x 4*2 ; interorbital breadth 9'4 ; breadth of brain- 

 case 21 ; palatal length 32 ; anterior palatal foramina 6*9 ; 

 breadth of palate outside m 1 19" 7. Upper tooth-series 29*3 ; 

 front of p A to back of m- 11. 



Hab. Katanga, Southern Congo basin. Type from the 

 Upper Lufira River. Alt. about 3600'. 



Type. Adult male. B.M. no. 7. 12. 13. 7. Collected 

 21st June, 1907, by Mr. S. A. Neave. 



Comparison with about forty skulls of Pelrodromus (s. s.) 

 from all parts of the range of the genus shows that this 

 animal from the north side of the Congo- Ilhodesian watershed 

 stands out markedly from all of them by its heavy muzzle 

 and large anterior incisors. Although adult the type is by 

 no means old, its teeth being but little worn. Many male 

 specimens with teeth more worn are among those with which 

 I have compared it, 



With regard to P. venustus itself, I am somewhat doubtful 

 if it ought not, like the Zululand form above described, to be 

 considered as a subspecies of P. tetradactylus, some of the 

 Nyasa specimens being more or less intermediate between the 

 two. But this question may be left for further material to 

 decide. 



Petrodromus tetradactylus sioynnertoni, subsp. n. 



General colour rather dark as compared with specimens 

 from Gorongoza and Beira, the cinnamon or hazel area of the 

 back less bright, the grey of the flanks more smoky, and the 

 buffy edging of the belly darker. Belly-hairs generally 

 washed with buffy. Upper part of thighs much greyer and 

 less buffy, the buffy of the flanks scarcely continued on to 

 them. In the other form this region is prominently buffy. 

 Upper side of hind feet rather lighter, though not so whitish 

 as in venustus. 



Dimensions of the type (measured on skin) : — 



Head and body 200 mm. ; tail 164 ; hind foot 53. 



Skull: greatest length 52; condylo-basal length 49; 

 zygomatic breadth 26*5; nasals 20'5 X 3*0 ; breadth of brain- 

 case 19'4 ; upper tooth-series 27'2 ; p i and two molars 9"7. 



Hab. Chirinda Forest, Melsetter, 8. Rhodesia. Alt. 3900'. 



Type. Adult male. B.M. no. 8. 7. 19. 10. Original 

 number 58. Collected 26th June, 1906, by C. F. M. Swyn- 

 nerton, Esq., and presented by him to the National Museum. 

 Eleven specimens. 



This race of Pelrodromus is readily distinguishable from 



