546 MR. O. THOMAS ON LAGORCHESTES FAsciatus. [Dee. 7, 
its lower side corresponding to the chin, no trace of such a prominence 
being present in any of the other genera. 
Tal natural correlation to this structure of the jaw, the lower 
incisors themselves have not the sharp inwardly projecting edges 
characteristic of those of the other Kangaroos, and are merely 
approximated to each other by their flat inner surfaces; the trans- 
verse sections of the incisors of the two forms (figs. 4 and 10) show 
this difference better than any description. 
The incisors and symphysis thus indicating a difference in the 
motion and use of the mandible, we should naturally expect an 
appreciable change in the shape of those parts of it by which it is 
attached and moved, and we therefore find, first, that the coronoid 
process possesses the very unusual character of having its anterior 
edge slightly concave in its upper half, all other Kangaroos having 
iis part evenly convex ; and, secondly, the condyle, Instead & 
having its length and breadth much about equal, is very much 
broader than long, and is provided with a broad, flat, supplementary 
internal process (compare figs. 5 and 11). 
Canines, present in Lagorchestes, are, as in the majority of the 
Macropodide, wholly absent in Lagostrophus. 
The two premolars of Lagostrophus, i. e. the smaller anterior deci- 
duous one, pm’ of the typical dentition, and the larger permanent one, 
or pm* (fig. 7), are both broad and flattened, their posterior decidedly 
greater than their anterior diameters, with well-developed internal 
edges, and with four or five shallow vertical grooves on their external 
surfaces. The premolars therefore correspond with the incisors in 
being broader and more flattened than is usual ; but the difference, at 
least in comparison with certain of the broader-toothed species, such as 
Macropus brachyurus, Quoy and Gaim., or Lagorchestes conspicillatus, 
Gould, is by no means so striking as in the case of the incisors. 
The molars appear to be precisely similar to those of Lagorchestes 
and the other smaller members of the Macropodine. 
The general shape of the skull (fig. 1) presents nothing very 
remarkable, except that, owing to the approximation of the two 
incisor series to each other, the premaxillee bearing them are very 
much narrower transversely than usual, and therefore give a peculiar 
slender and pointed appearance to the muzzle. 
With regard to the external characters, we have first to note that 
the rhinarium, notwithstanding the statements of Gould and Water- 
house, is really practically naked, as in the Wallabies, and is not 
hairy as in Lagorchestes*. The hair, in fact, only grows down the 
centre of the nose to the level of the superior internal angle of the 
nostrils, leaving the whole of the front of the nasal septum bare. 
The hind feet, instead of being short-haired as in Lagorchestes, 
are covered with long bristly hairs, very much as in Petrogale, 
these hairs nearly entirely covering up the narrow naked sole, and 
hiding the short, but strong and conical, central hind claws. 
? Even in Lagorchestes the hairiness is very variable, L. conspicillatus having 
a yery much less hairy muzzle than L. /eporotdes, the type of the genus. 
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