Page 54. 
270 ON HALMATURUS LUCTUOSUS. 
The cranial characters which distinguish Dorcopsis, as a genus, 
from Macropus, are not very significant. Looking at the base of the 
skull the arrangement of the teeth deserves attention. In Dorcopsis 
the premolar with the molars on both sides form straight lines, which 
are exactly parallel one to the other; whilst in Macropus the molar- 
premolar series form slight curves, convex outwards, converging 
behind as well as in front.. 
In Dorcopsis the zygomata are not so powerful or deep from above 
downwards, as in the similar-sized species of Macropus. A peculiarity 
also presents itself in the lateral occipital region, the exoccipitals 
descending considerably below the free extremities of the paramastoids 
in Macropus, whilst in Dorcopsis they reach downwards scarcely any 
further distance. : 
Respecting the teeth, Dorcopsis differs from Macropus in the much 
diminished size of the superior lateral incisors. The central incisors 
are not so broad, but nearly as long. The second incisor is very much 
smaller ; and though presenting a slight inflection in D. luctuosa, as 
mentioned above, this inflection is not, as in Macropus, posterior and 
internal, at the line of contact with the anterior margin of its more 
lateral neighbour. The third incisor is also very much smaller. The 
inflection on its labial or outer surface presents the same differences in . 
the two species of Dorcopsis that are found in the various species of 
Macropus: in D. luctuosa, as in M. brunii and M. thetidis, it is very near 
its posterior border; whilst in D. muelleri, as in M. major and most of 
the other species, it is far forward. 
The inferior incisors in Dorcopsis are proportionally narrower than 
in Macropus, in which peculiarity Dendrolagus resembles the latter 
genus: they, however, wear down in a similar manner, namely at the 
anterior end of the supero-lateral margin, differently from that in the 
Hypsiprymniform Macropodide, in which they wear in a rodent-like 
fashion. 
The presence of the superior canines in Dorcopsis distinguishes it 
from most of the species of Macropus, although they are almost as 
well developed in the subgenus Lagorchestes as in D. luctuosa, and in 
that one only. 
The premolars of Dorcopsis are particularly interesting, presenting 
characteristic features which are more suggestive of its affinities than 
any other skeletal point. As to those in the upper jaw, their breadth 
from before backwards is very nearly or quite as great as that 
of the first and second molar, together with the anterior of the two 
cusps of the third. The crown of the tooth on each side is prismatic 
in shape, with one of the angles forming the cutting-edge, the oppo- 
site side the base. A tubercle on the inner surface of the posterior 
end of the tooth disturbs the uniformity of the prismatic shape; it is 
