203 ^Ir. 0. Thomas — .4 revised 



subgcucrically separated, thus making three subgenera, as 

 follows : — 



3 a. Otomys, s. 8. 



Genotype. 0. irroratus, Bts. 



First lower molar with four laminae ; last upper with 

 5 to 8. 



3 b. Ancuotomts *, subgen. nov. 



Genotype and only species. 0. anchieta, Boc. 



First lower molar with five laminae ; last upper with seven. 



3 c. Lamotomys t, subgen. nov. 



Genotype and only species. 0. laminatus, Thos, & Schw. 



First lower molar with 6-7 laminre; last upper with 9-10. 



Otomys contains the great mass of the species of the 

 group, and has by far the largest range, extending from the 

 Cape to Abyssinia, while the other two genera are both 

 confined to South Africa. 



The following new forms of this genus appear to need 

 description : — 



Otomys iri'oratus ccenosus, subsp. n. 



Size averaging very large, the skull-length of large speci- 

 mens greater than in any other Otomys. 



Colour a dark muddy greyish, darker than in 0. i. auratus, 

 greyer, especially on the sides and rump, than in true 

 irroratus. 



Skull as in true irroratus, but averaging larger. Laminae 

 of »i' always 6 in number. 



Dimensions of the type (measured in the flesh) : — 



Head and body 201 mm.; tail 125 ; hind foot 32-7; 

 ear 23*5. 



Skull : greatest length 46'3 ; condylo-incisive length 43*5 ; 

 zygomatic breadth 23'2 ; nasals 20*5 X 9*2; iuterorbital 

 breadth 4 ; upper molar series 9*2. 



Hub. Kuruman, Bechuaualand. Alt. 4000'. 



Type. Adult male. B.M. no. 4. 4. 8. 13. Original 

 number 20. Collected 14th February, 1904, by R. B. 

 Woosnam. Seven specimens. 



By their great average size and muddy-grey colour these 

 Otomys seem distinguishable from the ordinary 0. irroratus, 



^ * ayx'j near-|-0^o?«ys. 



j- Xd^os, tlie maw (also voraciousness) -|- 0<o/ny«. 



1 



