
279 
ridge and the postfrontal. The antero-posterior extent of the temporal fossee and the 
calvarian interval between them are alike in both species. But it is in advance of 
this part of the skull that the greater differences begin. ‘The orbits are smaller; the 
breadth of the cranium across the postorbitals is less; the fore part of the cranium is 
modified for the support and attachment of a much weaker and shorter mandible, 
The premaxillary part (Pl. LX XVIII. figs. 4, 5, fig. 1, 22) of this mandible is fortunately 
nearly entire. ‘Che anterior undivided mandibular part of the base is much smaller and 
shorter in proportion to the nasal process, The perforated irregular surface in relation 
to the bill-sheath contracts posteriorly more gradually between the nasal and maxillary 
branches to form the smoother prenarial septum; and this is relatively of much less 
extent than in J. rheides. 
The palatal surface of the premaxillary in D. casuarinus (ib. fig. 5) is flatter and less 
bent; the marginal alveolar grooves are shallower. The mid furrow upon the narrower 
beginning of the nasal process is long and deep; it disappears upon the hinder flattened 
part of that process. 
The tympanic (Pl. LX XVIIL. figs. 1, 98 & 13), like the mandible it supports, is markedly 
less than in ), rheides. ‘There is less indication of a division of the single condyle that 
crowns the antero-posteriorly compressed mastoid branch (e); the orbital or pterygoid 
branch (#) is broader and shorter, more convex outwardly, more concave at the inner 
side, with a better-marked and more prominent pterapophysial facet (p). The pneu- 
matic depression, though smaller, is better defined, extending from the foramen upward 
to the inner side of the mastoid condyle. 
The rami of the lower jaw (fig. 6) are more delicate and slender in proportion to 
their length than in D. rheides. The back part of the ramus is less expanded, the outer 
border of its concavity is thicker and more obtuse, the inner one is less thick, the two 
borders, which meet at the lower angle, being more alike in character. ‘The articular 
surfaces and intervening vacuity offer no notable modification. The outer depression 
between the angular and surangular retains posteriorly a small vacuity leading obliquely 
upward to a foramen on the inner side of the ramus, grooving the base of the low obtuse 
coronoid process. ‘The splenial element (81) has coalesced behind, not sia a 
dentary has coalesced with both the angular and surangular, The outer mid tract o 
the symphysis (fig. 7) is defined, as in other species, by a pair of parallel oor a 
The more characteristic leg-bones of the specimen to Wiis ee oe e eS . 
belongs, agree pretty closely in size with the type specimens', but are rather | 
: . Pe ht ‘ ant’ surements 
slender as in the smaller variety of Dinornis casuarinus in Dr, Haast’s admea : 
in. lines. 
the following being the length of— 
8 o 
M t t fi - . . . * . . 4 - . . 
Tibia 4) pes Min Bas h as might be 
The difference between Dr. Haast’s larger and smaller sizes 1s only such 
tener ‘ , . XL. fig, 3. 
| Femur, Pl, XXXVIIL, figs. 1-3; tibia, Pl. NXXIX. fig. 2; metatarse, Pl Ae 

