BY R. BROOM. 



49 



about that of .Ifaoroptis ualibatus, but the dental details are 

 decidedly different. Of existing species the only one to which it 

 comes at all close is M. ayilis; but from this species it differs 

 in the narrowness of the molars and in the jaw being considerably 

 thinner. Among extinct forms the only ones approaching it in 

 dental details and measurements are some fragmentary specimens 

 from Queensland, referred to by De Vis.* Thinking my form 

 might possibly belong to the same species as one or other of the 

 fragmentary Queensland specimens, I submitted a specimen to 

 Mr. De Vis, who kindly writes me as follows :— " I have com- 

 pared the Halmaturus jaw with my types — it agrees with none 

 of them. In size and general features it is like H. agilis, but 

 appears to me to be quite distinct from that species." As my 

 specimens thus appear to differ from all existing or previously 

 observed extinct species, I have conferred on it the above dis- 

 tinctive name from the locality in which the form has first been 

 observed. 



In general form the lower jaw resembles that of the larger 

 Wallabies; there is, however, a greater disparity between the 

 anterior and posterior depth of the jaw than is usually the case 

 in existing forms. The dental portion of the jaw is comparatively 

 narrow — more so than in any of the existing larger Wallabies. 

 The angle is more inflected than in the Wallabies, closely 

 resembling the condition in the Rock- Wallabies. The premolar 

 (p*) is well developed, rather narrow without internal cusp. It 

 is slightly ridged, there being three very shallow vertical grooves. 

 In the specimen figured (PI. vi. fig. 3) there are also on the outer 

 aspect two small horizontal furrows. The molars resemble very 

 closely those of M. ualahatus — the crests being curved and the 

 links well developed. 



Though two specimens illustrate the palatal region, in neither 

 are the teeth well preserved. The upper premolar (p*), however, 

 appears to have had a moderate internal cusp. One point of 

 ^reat interest is the presence of large palatal vacuities. In this 



* Proc. Linn. Soc. N.S.W. (2) Vol. x. (Pt. i. 1895'. 

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