Mem. Nat. Mus. Vict., IX, 1936. 
TWO NEW RATS FROM CENTRAL AUSTRALIA. 
By C. W. Brazenor, 
Mammalogist, National Museum. 
(Plate I.) 
The two new rats described below were kindly handed over 
with other mammals by the Zoology Department of Melbourne 
University, and are part of the late Sir W. Baldwin Spencer’s 
Horn Expedition Collection, which is now completely housed 
in the National Museum. 
When the late Edgar R. Waite dealt with the Horn 
Expedition Muridae (1) he assigned one form to Rattus greyi 
Gray but said, “I am scarcely satisfied with the identifica- 
tion.” Wood Jones (2) has since pointed out that Gray’s 
original description of the species is quite unlike that of 
Ogilby (3) ; Ogilby’s description was used by Waite in his 
identification and it is obvious that the Horn Expedition 
specimens cannot be associated with Gray’s species. They 
are, in fact, very closely allied to Rattus tunneyi. The latter 
was described by 0. Thomas (4) in 1904 from specimens col- 
lected by J. T. Tunney on the Mary River, about eighty miles 
south-east of Darwin, where tropical conditions exist and 
there is a rainfall of between 50 and 60 inches yearly. As 
might be expected, Central Australian specimens from Alice 
Springs, in true desert with a rainfall of about 10 inches, 
exhibit discrepancies. They are therefore described as 
Rattus tunneyi dispar subsp. nov. 
Mus greyi Waite (nec. Gray), Kept. Horn Expdn., ii, p. 401, pis. 25 and 
26, fig. 3, 1896; id. Proc. Roy. Soc. Vict., vol. x, p. 124, 1897. 
? Rattus greyi Wood Jones, Mamm. Sth. Aust., iii, p. 305, 1925. 
A densely furred rat; general colour about sayal brown. Dorsal fur 
(16 mm.) vinaceous slate for more than two-thirds of its length, subterminal 
band clay-colour with hazel tips. Side of body lighter. Head as body; 
cheeks lighter, upper lip white. Mystical vibrissae sparse and short (longest 
30 mm.); mixed white and brown hairs. Ears small, rounded in outline; 
inner surface with a few silvery hairs, outer surface with sparse adpressed 
hair coloured as body. Ventral surface of body creamy white, hair white to 
base. Tail shorter than head and body, brown above, whitish below, not 
contrasted; uniformly clothed with hairs two scales in length not sufficiently 
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