52 MR. A. H. GARROD ON HALMATURUS LUCTUOSUS. [Feb. 2, 
that of D. muelleri, the following being the two most important mea- 
surements in adult specimens of the same sex (female) :— 
w: luctuosa. De muclleri. 
In. in. 
Length of skulle: ia. dV F224 AS 4°] 4°55 
Greatest breadth, from zygoma to 
ZY ZOWMA' eye eleveleleie eters SUSE RS 2°2 2°03 
In some minor details there are slight differences. In D. mueller, 
as in most species of Macropus, the premaxillary region is bent 
downwards in such a way that the line formed by the trenchant 
edges of the molar teeth, if projected onwards to the nose, is quite 
above the incisor teeth. In D. ductuosa this bending downwards of 
the snout is not so marked, as will be seen by comparing the side 
view of the skull (Plate VII. fig. 3) and the similar one of D. muelleri 
in Prof. Miiller’s elaborate work above referred to. 
The palatine foramina, one large one on each side, together with 
several much smaller ones behind each, in D. muellert end behind 
the transverse palato-maxillary sutures, whilst in D. luctuosa their 
anterior margins are formed by the palatine plates of the maxillary 
bones, into which they encroach a short distance. In D. luctuosa 
the upper of the lacrymal foramina in each lacrymal bone has an 
ossific ridge behind it, which causes it to be completely exserted, or 
situated on the face outside the orbit; whilst in D. muwelleri the 
absence of this bony ridge causes it to be situated in a recess on the 
margin of the orbit. In D. luctuosa the apex of the augular 
process which is developed downwards from the inferior margin of 
the maxillary portion of the zygoma, is opposite the anterior cusp of 
the third molar tooth, whilst in D. mnelleri it corresponds to the 
posterior cusp of the second molar. 
With regard to the teeth themselves, the canines in D. muelleri 
are quite the size of or even slightly larger than the most lateral 
incisor; in D. luctuosa, however, they are much smaller, being 
nothing more than slightly curved dentine cylinders about =) of 
an inch in diameter, as in the subgenus Lagorchestes, and directed 
downwards and forwards. In both the species the third incisor has 
an inflection on its labial surface, as in all the species of Macropus: 
in D. muelleri this fold is a little in front of the middle of the tooth ; 
and in D. luctuosa it is decidedly nearer the posterior border. In 
the last-named species there is a similar distinct inflection on the 
second incisor; in D. muelleri this is not apparent. In D. muelleri 
the inferior incisor is directed more immediately forward than in 
D, luctuosa, in which it turns slightly upwards; this peculiarity is 
correlated with the difference in the obliquity of the premaxillary 
region (vide Plate IX.). 
In the enormous premolars there is a slight difference—those of 
D. muelleri being a little the larger, in the upper jaw having a 
breadth of 0°55 inch against 0°475 inch for the same teeth in 
D. luctuosa. In D. muellert the bony septum between the two fangs 
of each premolar, especially of the lower jaw, is particularly con- 
