120 
FOSSIL JAWS OF MACROPODID.K, 
dimensions, which demand its identification with H. dorsatis, and 
as dimensions alone are a good servant but a bad master it would 
be a very rash step to announce on the evidence of this imperfect 
mandible the geological antiquity of the common scrub wallaby. 
Halmaturus sp. 
Molars with curved crests, rounded angles and strong links; 
smooth. Lower molars with an incipient posterior groove, but 
no talon. 
Dimensions. 
Mandibular. — The last two molars are 16*0 in length. The 
width of m. 3 5*4. Thickness 8-7. 
These dimensions have no counterpart among known species. 
Examples. 
A portion of an adult left ramus with m. 3 , m. 4 — A portion of 
a young right maxilla with mp. 4 (part), m. 1 , m. 2 may be pro- 
visionally referred to the same species. 
Halmaturus sp. 
The anterior portion of a young ramus with m. 2 and relics of 
m. 1 , the molars with rectilinear crests, angular lobes and feeble 
links, and the length of m. 2 barely 6'0 is insufficient for determi- 
nation. 
Macropus magister, n.s. 
M. titan, Owen, partim — Owen, XXII. Vol. ii. p. 360; II. PI. 82, 
figs. 17-18; Lydekker, IV. p. 225; Etheridge, V. 183. 
The validity of a new name for the paramount species among 
the kangaroos of the Nototherian Period depends on the proof to 
be adduced that the fossils referred by Owen to his species, M. 
titan, are by no means identical with it. The name M. titan was 
given by its author to a species represented by a portion of a 
young mandible with a single perfect tooth, m. 2 (m. 1 of II. PL 
82, figs. 17, 18). With such straitened means of recognising the 
species in other examples it might have been supposed necessary 
