BY EDGAK R. WAITE. 581 



appears to be rather more external. The relative position of each 

 row of teeth is slightly different owing to the narrower snout ; 

 instead of forming nearl}'^ straight lines, they converge somewhat 

 anteriorly. In the lower jaw the premolar is in the same line 

 with the molars, whereas in D. lumholtzi it inclines outwards. In 

 this species also the external opening of the dental foramen is 

 large and constitutes a direct perforation. In D. hennettianus it 

 is small and deeply sunk, and the mental foramen is placed more 

 forward, quite in advance of the premolar. 



Being suspicious that this skull was abnormal as far as the 

 prenasals and postfrontal are concerned, I had one extracted 

 from a dried skin. This is unfortunately so battered about the 

 muzzle as to render that portion useless for comparative purposes. 

 There is no postfrontal and the fronto-parietal suture is rounded 

 behind : it is therefore highly probable that the prenasals of the 

 skull first examined may be only a dismemberment of the nasal. 

 The damaged skull is from an immature animal and differs from 

 the adult in having the fronto-parietal crests scarcely discernible 

 and widely separated. The interorbital space is also propor- 

 tionately broader. 



Collett writes of D. lumholtzi* : — " Somewhat to the front end 

 of the interparietale, each parietale is perforated by a foramen 

 [which I cannot discover in the other Macropodidce which have 

 come under my notice] ; in the skull of a young individual 

 [length 106 mm] it is indistinct on one side." 



In all our specimens this foramen occurs on both sides, but not 

 in all cases in the same relative position. Such foramina also 

 exist in D. beniieMianus and are placed slightly behind the front 

 front edge of the interparietal. 



Collett also says — " The palate is entire, and has no foramina 

 palatina." One onl}^ of our examples shows a single inconspicuous 

 foramen, but in both our skulls of I), hennettianua the posterior 

 palate is perforated by two vacuities man}' times larger than the 

 posterior palatine foramina. 



* Zool. Jahrb. ii. 1887, p. 900. 



