BODEN KLOSS: Rats and Mice. 121 
1 © Bima Soembawa 
2 Wy Oreilelok  Betons S. Sumatra 
1¢72 Palembang 3 
ROIS à (Talangbetoetoe) S. Sumatra 
2 © Benkoelen W. Sumatra 
i & 1 © Tapanoeli 5 
4 9 Djambi E. Sumatra 
Teti @ Iene À 
1 S 1 © Kotaradja N. Sumatra . 
Sk oe Bangka 
1 4 1 © Poeloe Toedjoeh, between Bangka and Singkep Ids. 
3 d 3 Q Serasan, South Natoena Ids 
Dd Singkawang W. Borneo 
1 #1 © Mempawa 
This is the house-rat of Malaysia. 
The individual variation is very great and in the series listed above 
together with an equally large series from the Malay Peninsula there seem 
to be no characters which belong solely to any one particular locality : 
thus I find it impossible to recognise any local races in the material 
examined. Not only are there great differences of colour but the cranial 
characters are also unstable: for instance, in a series from one place there is 
a marked difference in the size and shape of the bullae The upper pelage 
is brown streaked with brownish black but the ground-colour varies from 
bright ochraceous to isabelline or dull brown. The variation of colour below 
is greater still and the ventral surface may be buffy-white, buffy, fawn, pale 
grey, dark smoky grey, isabelline, rusty, drab, hair-brown, or combinations 
ot these; frequently one colour is washed with another; sometimes there 
is a dark gorget and a dark median line down the abdomen. The ventral 
fur is often rather harsh and adpressed, more so than in the field rat. 
The feet are either pure white, white washed with ochraceous, dark mesially 
with the sides and digits pale, or entirely dark. The tail is always dark throughout 
and fairly well clad with short hairs, generally more so than in the field-rat. There 
are always ten mammae in the females — 2 pairs pectoral and 3 pairs inguinal. 
On the whole the Sumatran series is more rusty beneath than the 
others, but with one exception it is exceeded in this respect of the 
two specimens from Onrust Id. 
The Buitenzorg Museum material is unfortunately without measurements 
but it does not appear from the dimensions given by DAMMERMAN (l.c. ) 
that there is any difference in the proportions of tail to head and body 
length between Javan and Malayan individuals. 
Though a house or town rat this from is occasionally found in cultiv- 
ated land near buildings and villages where it probably breeds with the 
true field or country rat — this cross-breeding producing individuals which 
it is difficult to allocate. 
