the Genus Otomys. 277 



two known forms of the group with doubly grooved lower 

 incisors. 



(17) O/oinijs Dartmouthi. 



Otomi/s Dartmouthi, Tlio.s. Ann. Sc May. Nat. Hist. vol. xviii. p. 141 

 (1900). 



6. 7. 1. 61-67. Ruwenzori Exploration. Alt. 12,500'. 



Rather smaller and darker in eolour than tijpus. The 

 normal dimensions are : — 



Head and body 150 mm. ; tail 90 ; hind foot 26'5 ; ear 25, 



Skull : greatest length 39; basilar length 31 ; zygomatic 

 breadth 20; length of upper molar series 8 ; bullse 7. 



The presence of only six laminae in m^ suffices to separate 

 this species from any other known member of the group 

 with double grooves on the lower incisors. 



Section III. 



The two aberrant species in this Section seem to be found 

 isolated in the midst of normal forms : laminatus has been 

 taken only from Sibudeni, Znluland (and, it is stated, from 

 a locality in Pondoland), and we have qnite normal irruralus 

 from the same place ; Anchietce is recorded by Bocage from 

 Caconda, &c., Angola, and has not been found elsewhere 

 outside Angola ; while we have a specimen from Braganza 

 which is apparently a normal irroratus, and Bocage records 

 several other localities in Angola in which irroratus has 

 been found. 



(18) Otomys Anchieta. 



Otomys Anchietce, Bocage, Joru. Sc. Acad. Lisb. ix. 1882, p. 26. 



92. 1. 9. 12 ; 97. 3. 6. 10 (in al.). Caconda, Angola. 



A large Otomys Avith the brown colouring of the northern 

 forms of «To>v/^M5 and iu addition an almost red colouring 

 {I'oux ardent of Bocage) on face and rump. The dimensions 

 are : — 



Head and body 200 mm. ; tail 120; hind foot 37 ; ear 24. 



Skull : greatest length 47 ; basilar length 39 ; zygomatic 

 breadth 26 ; length of upper molar series 11 ; bullae 10. 



This is the largest form so far recorded in the genus ; it 

 is larger even than the biggest irroratus from Kuruman both 

 in body and skull dimensions, yet the Kuruman specimens 

 are very old, while the specimens of Arichietce though mature 

 are not by any means old. But for its aberrant m^ 

 Anchietce would fall into Group 1 of Section II., i. e. the 

 forms having one deep and one shallow groove on each lower 

 incisor. 



Ann. d; Mag. N. Hist. Ser. 7. Vol. xviii. 20 



