10 FreLtp MusEuM oF NATURAL HIstorY—ZOoO.LoGy, VoL. X. 
Otomys angoniensis elassodon subsp. nov. : 
Type from Naivasha, British East Africa. No. 16684, Field Mu- 
seum of Natural History. Adult female. Collected January 29, 
1906, by E. Heller. 
Characters. Similar to Otomys angoniensis, but paler and more 
grayish; molars narrower; nasals broadly expanded; m* with seven 
lamine. Distinguished from Otomys nytke canescens by slightly 
darker color but especially by more elongate skull, narrower brain- 
case, and narrower molars. 
Measurements. Type: Total length 270; head and body 183; 
tail vertebre 87; hind foot (c. u., dry) 29; ear 21. Skull of type: 
Greatest length 41; basilar length 34.3; zygomatic breadth 21; 
length of nasals 17.7; greatest breadth of nasals 8.9; least inter- 
orbital breadth 4.5; depth from highest point of orbit to alveolar 
border at front of m® 13.8; postpalatal length 15; palatine slits 8; 
maxillary toothrow 8.2; greatest width of m1 2.4. 
Otomys nyikz canescens subsp. nov. 
Type from Kijabe, British East Africa. No. 16682, Field Museum 
of Natural History. Adult male. Collected January 20, 1906, by 
E. Heller. 
Characters. Similar in size and cranial characters to Otomys 
nyike, but color much paler and grayer; general effect of upperparts 
grizzled wood brown or broccoli brown instead of deep russet; nasals 
broadly expanded anteriorly; m% with seven lamine. Color much 
as in Otomys a. elassodon, but slightly more grayish; skull shorter 
and broader; molars wider. 
Measurements. Type and two topotypes, respectively. Total 
length 259, 255, 242; head and body 175, 165, 157; tail vertebre 
84, 90, 85; hind foot 29, 30, 27.5; ear 19.5, 21, 20. ‘Skull of type: 
Greatest length 37.2; basilar length 30.9; zygomatic breadth 19.6; 
length of nasals 17.1; greatest breadth of nasals 8.5; least inter- 
orbital breadth 4.6; depth from highest point of orbit to alveolar 
border at front of m* 12.8; postpalatal length 13.8; palatine slits 
6.8; maxillary toothrow 8.4; greatest width of m1 2.6. 
Arvicanthis barbarus convictus subsp. nov. 
Type from Voi, British East Africa. No. 17206, Field Museum 
of Natural History. Adult male. Collected April 16, 1906, by 
E. Heller. 
Characters, Allied to Arvicanthis barbarus spekei, A, b. zebra and 
other forms having unbroken stripes. Size about as in speket but 
