314 Mr. O. Thomas on 



SkuU-cllmenslons of the type : — 



Oomlylo-basal length 67 mm. ; condylo-inclsive length 6G ; 

 zygomatic breadth 48*7; nasals 25x8"7; anteorbltal fora- 

 men 6*2 X 5 ; greatest breadth on tVontals 18"7 ; interorbital 

 breadth 10"5 ; height of crown from alveolus of nt^ 27'8 ; 

 occipital plane, height from basion 22'5, breadth 33 ; palatilar 

 length 37*2 ; palatal foramina 6"7 ; upper molar series 

 (crowns) 152 ; breadth of m^ 5"6. 



Hub. Eastern Burma and Yunnan. Type from Yunnan, 

 probably from the neighbourhood of Mong-tze. 



Ti/pe. Adult female. B.M. no. 12. 7. 25. 42. Original 

 number 4. ( !olkcted 9th June, 1910, by H. Orii. 



Distinguished from R. pru'mosus by its greater size, this 

 species is sejiarable from R. sinenNis by the definitely hoary 

 character of its fur, that animal being practically witliout the 

 white-tipped longer hairs which give so marked a character 

 to R. pridnosus, latoucJiei, and senex. In this respect, there- 

 fore, R. si)iensis apj)roaches the unicolor soft-furred Chinese 

 species R. vestilus and davidi. 



Cannomys. 



The uncertainty about the identity of Blyth's Rhizomys 

 castaneus, said to be from " Arakan/' has hitherto prevented 

 consideration of the different species and races of Cannomys. 

 Now, however, the examination of the specimen sent by 

 Dr. Annandale as typical of castcmeus * enables me to make 

 a preliminary attempt at the arrangement of the group — but 

 it is very far from complete or satisfactory. 



The specimen of 6'. castaneus is skull no. 403 of the Indian 

 ^luseum, and I find it closely agrees with examples in the 

 ]3ritish Museum from Thaton, 'i'enasserim, and is clearly 

 the same form. Whether the species is really to be found 

 in Arakan remains to be seen when that little-known country 

 is properly explored. 



Tlianks to the splendid work of the Bombay Natural 

 History Society, series of these red bamboo-rats have been 

 obtained on the Chiudwin, in the Shan States, and on 

 Mt. Popa, thus effectively suj)plenienting those whicli t!ie 

 Museum possessed trom Sikkim, Manipur, Siam, Tenasserim, 

 &c. 



Externally there is little difference between the different 

 local forms. All are of similar proportions and all, with one 

 exception, have the coat washed terminally with some shade 

 of rufous, which may be brighter in some and deeper in others, 



* Iihizo7nys castaneus, Bljth, J. A. S. B. xii. p. 1007 (1813> 



