18 ARKIV FÖR ZOOLOGI. BAND 8. NIO 23. 



As seen by the above given measurements the skull of 

 the Sakerat specimen is partly intermediate partly consider- 

 ably smaller than either those of Mus surifer Miller or 

 Mus surifer leonis Rob & Kloss. According to the lack of 

 material of specimens from Eastern Siarn I am for the present 

 unable to state if it is a new subspeeific form, or not, which 

 inhabits those parts of the Kingdom which were visited by 

 my Expedition. 



19. Epimys rufescens Gray. — A single specimen of 

 this rat was obtained at Sakerat in Eastern Siarn during my 

 stay there in January 1912. 



During my stay in Siarn I only got very few smaller 

 mammals and especially råts and mice. The only way to 

 get them is to use traps, but I either löst my traps, or got 

 the trapped specimens destroyed by ants which, of course, 

 were very numerous in every part of the country. 



Cranial measurements: 



Greatest length = 45, o mm. 



Length from condylus to gnathion = 42, o » 



Basicranial length = 35,6 » 



Zygomatic breadth = 20, o » 



Least interorbital breadth = 6,5 » 



Length of diastema =11,7 » 



Greatest width of brain-case =17,2» 



Length of nasals = 15,9 » 



Greatest breadth of nasals = 4,5 » 



Palatilar length = 20,0 » 



Length of palatilar foramina = 8,8 » 



Breadth of combined foramina = 3,8» 



Length of maxillar toothrow = 7,1 » 



20. Mus concolor Blyth. — Blyth: Jonrn. As. Soc. 

 Bengal XXVIII, 1859, p. 295. — Of this species, which is 

 very common in the Burmese countries, I also got a speci- 

 men during my stay at Sakerat. In both colour and size it 

 agrees perfectly well with some specimens from Kariman now 

 in the British museum. The skull, however, shows greater 

 dimensions than specimens from Kariman, which may be 

 seen by the measurements given below. 



