380 MR. C. BODEN KLOSS ON 
Characters :—A general colour resemblance to the “rattus” rats 
of the southern parts of Siam but the skull relatively broader and 
the bullae much smaller. Mammae 3-—3=12, as in R, r. thai mihi, 
from Central Siam, but the skull broader throughout and the bullae 
smaller while the colour of the upper parts is darker, 
Colour. Above mingled bright ochraceous-tawny and black- 
ish, the sides greyer; below white. Feet white, the metapodials 
slightly darkened mesially. Tail brown. 
Skull and teeth. Like those of R. rv. neglectus of Siam but 
the skull markedly broader in all respects — palate, zygomata, basi- 
occipital, etc.; nasals broader, flatter, more spatulate anteriorly ; 
bullae considerably smaller and Jess dilated ; palatal foramina large. 
As compared with R. r. thai there is less difference in the size of 
bullae but the skull characters and the colour distinguish it. 
Measurements. See table poste s. 
Remarks. The external colour differences are hardly sutt- 
cient to separate this race from the local neglectws rat and I might 
have regarded the number of mammae as abnormal, bub the skull is 
so different in its greater relative breadths, shape of nasals and 
diminutive bullae, that there is no doubt of its distinctness. 
The immature female is dark brown above and dark grey 
on the sides, only slightly speckled, 
Type. Adult female (skin and skull) No. 2196/ C. B. K. 
Collected at Lat Bua Kao, East Siam on 19th October 1916. 
41. Rattus concolor 
Mus concolor, Blyth, Journ, Asiat, Soc. Bengal, XX VILI, p. 295 
(1859). 
Epimys concolor, Kloss, P.Z.8, 1916, p. 57. 
Rattus concolor, Gyldenstolpe, Kungl. Sv. Vet. Akad. Handl. 57, 
No. 2, p. 45, (1917) ; Kloss. Journ. N. H. Soc. Siam, IIT. p, 62 (1918). 
6 adult and 2 immature examples from Koh Lan, 
Evidently a common house animal for the village children, 
seeing that I wanted rats, brought this species in large numbers in 
a very short time; the majority, however, were young examples 
taken from the nest. 
[ have examined Blyth’s original series (vide Records Ind. 
JOURN, NAT, TLIST, SOC, SIAM. 
