1060 JOURNAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXVlll. 
Sharply contrasted with all other Indian forms of Raitus by its 
large size, great weight and robust and strongly ridged skull, this 
extremely interesting rat presents a strong superficial resemblance to 
R. norvegicus, now the Common Eat of Europe. Hodgson, deceived 
by this likeness, thought the present animal “ as nearly allied to 
decumanus as ” Bandicota nemorivaga is “ to the Bandicoot ” ; and 
since, to within a few days ago, the skulls of his specimens remained 
concealed within the skins, no subsequent writer appears to have had 
any more accurate notion of its affinities. This form puzzled me very 
much when I was preparing my former account of the House Rats of 
India, and in the end I thought it better to await the coming of modern 
material from Nepal before attempting to deal with it. 
The specimens collected by the Survey in Nepal agree exactly with 
those collected by Hodgson in that country eighty years ago ; and it 
is now perfectly clear that brunneus is a form of R. rattus and has 
nothing whatever to do with R. norvegicus. If it were not for the fact 
that some of the specimens [e.g., Ferping No. 237, Godaveri No. 134, 
and all those from Changoo) have pure white bellies and that their 
skulls were slightly smaller than those of dusky bellied brunneus (see 
Table II), one could regard brunneus as a full species of the rattus 
group, confined to Nepal. But the specimens just mentioned are 
on the whole intermediate between brunneus on the one hand and 
brunneusculus and other Indian subspecies on fhe other, although it 
is to be noted that the skull proportions, apart from the absolute size, 
remain much the same in both light-bellied and dark-bellied brunneus. 
Personally I am inclined to think that brunneus is a local “ parasitic ” 
development from the true wild form [R. r. brunneusculus) of Nepal. 
Bv becoming more strictly commensal with man these rats have 
obtained access to larger food supplies ; with increased nutrition there 
has come increased bodily size. On the other hand parasitic habits 
have had their usual effects upon the skull ; the temporal muscles have 
become relatively weak, so that the ridges marking the upper limits 
of the origins of those muscles are less closely approximated post- 
eriorly than in the wild form ; the tooth-rows shortened, etc. The 
unusual thickening of the frontal beads is also I think a character of 
degeneration, comparable, perhaps, with that peculiar thickening of 
the supraorbital ridges seen in monkeys which have lived in captivity. 
5. Rattus rattoides, Hodgson. 
1841. Mus rattoides, Hodgson. J. A. S. B., x., p. 915 (no descrip- 
tion.) 
1845. Mus rattoides, Hodgson. Ann. Mag. Nat. Hist, xv., p. 267. 
1891. Mus rattus, Blanford (in part.) 
1914. Epimys vicerex, Wroughton {nec Bonhote). J. B. N. H. S., 
xxiv. p. 489. 
