438 SPALACID,T.. 



Genus RHIZOMYS, Gray, 1831. 

 Syn. Nyctocleptcs, Temm. 



Form robust ; eyes very small ; ears small and naked ; thumb 

 very small, rudimentary, but furnished with a claw. Tail almost 

 naked, having only a few scattered hairs, and not scaly, about one 

 fourth to one third the length of the head and body. 



Dentition : i. '^ m. gE^. The upper incisors are arched forward 

 and both they and the lower incisors are usually deep orange in 

 colour ; occasionally, however, the upper incisors are white, the 

 lower orange. There are no premolars. Vertebrae : C. 7, D. 13, 

 L. ?, S. 4, C. 19 (in R. hadlus). There are 3 pairs of inguinal and 

 2 pairs of pectoral mammse. The anatomy has been described by 

 Anderson (An. Zool. Ees. p. 314). 



Three distinct forms occur within our hmits. Eemains of a 

 fossil species have been found in the Siwalik beds. 



Synopsis of Indian and Burmese species. 



A. Head and body 7 to 8 inches ; colom' chestnut 



or dark brown, not grizzled R. badius, p. 438. 



B. Head and body 10 to 14 inches ; colour dark 



brown, jirizzled i?. i^uinosus, p. 439. 



C. Head and body 15 to 19 inches; colonr dark 



ashy to light brown B. sumatrensis, p. 439. 



312. Rhizomys badius. The bay Bamhoo-Rat. 



Rhizomvs badius, IIod(/son, Qdc. Jown. JV.H. ii.pp. 60,410 (1842); 



Bhjfh',J. A. S. B. xii,p. 925 ; id. Cat. p. 122 ; Jerdo», Mam. p. 214 ; 



A^iderson, An. Zool. Res. p. 329, pis. xiv, xvi ; Thomas, P. Z. S. 



1880, p. 65. 

 Rhizomys minor, Gray, A. M. N. H. x, p. 266 (1842) ; Horsf. Cat. 



p. 105 ; BlytJi, Mam. Birds Burma, p. 41 ; Anderson, An. Zool. 



Res. p. 327, pis. xv, xvi. 

 Ehizorays eastaneus, Blyth, J. A. S. B. xil, p. 1007 (1843); id. Cat. 



p. 123 ; id. Mam. Birds Burma, p. 41 ; Blanford, J. A. S. B. xlvii, 



pt. 2, p. 165. 



Ytikron, Kakhyen ; Khai, Burmese. 



Pur soft and rather thick. Ears hidden by the fur. Foot-pads 

 smooth, not tuberculated. 



Colour cliestnut, bay or ashy brown, but nearly uniform in each 

 individual, rather brighter and deeper above than below. All the 

 basal portion of the fur, two thirds to three foui'ths or more, dark 

 cinerous or leaden grey. Sometimes there is a white spot on the 

 forehead. In most young specimens and some adults the tips of 

 the hairs are dull rufous or ashy brown (R. minor). 



Dimensions. Head and body 7 to 9 inches, tail about 2-7, hind 

 foot from heel 1-3, both sexes the same ; basal length of skull 1*85, 



