

273 
found the nasal confluent with the frontals in all other specimens of skulls of more or 
less adult birds; they are planed off, as it were, above, to let in the nasal process of the 
premaxillary. Such depressed articular surface (Pl. LXXYV. fig. 3, 15) does not reach 
further back than the trausvere parallel of the lachrymal part of the orbits, 
The prosencephalic part of the cranial cavity makes a prominence above the general 
level of the calvarium, The postfrontal (ib. fig. 1, 12) is nearly vertical. The temporal 
fossa 1s narrow antero-postettorty compared with that in Dinornis éelephantopus, but is 
relatively wider than in D, erassus: a postcrotaphyte fossa is defined by a short, pre- 
mastoid, pointed process’. The mastoid process (fig, 1,8) is long, subcompressed from 
before backward, and pointed. 
The rostral part of the premaxillary (ib. 22) is relatively longer than in D, erassus ov 
D. elephantopus, shorter than in D. robustus; it is minutely perforated, showing a cork- 
like surface ; that of the nasal process (22') resumes the usual smoothness, as does the 
premaxillary part of the internarial septum (s). The premaxillary is more suddenly 
pinched in, as it were, laterally, to form this septum, than in any of the above species . 
its fore-and-aft extent is two-fifths that of the premaxillary prior to its trifurcation. The 
entire portion of the bone forming the end of the upper mandible is slightly deflected, 
and terminates subacutely. The upper median tract is defined by a well-marked, 
though shallow and narrow, groove on each side, ending about four lines from the apex. 
The palatal surface shows a low, narrow or linear median ridge, and two wider marginal 
or alveolar grooves; between these grooves the surface is transversely concave at the 
middle, and convex on each side. At about an inch from the apex the mid ridge sub- 
sides, and the bifurcation of the palato-maxillary processes begins; the fissure is rela- 
tively longer and narrower than in Dinornis robustus, ‘The narrow base, or beginning, 
of the nasal process (fig. 1, 22’) shows a linear mid furrow on its upper surface, which 
disappears as the process flattens and expands; the under surface of the process shows 
a low mid ridge, against which the margins seem to be bent or folded inward to form 
the front part of the internarial septum. ‘The hind free concave margin of this septum 
shows the fissure left between the inflected laminw, which diverge below to form the 
upper surface or layer of the palatal part of the premaxillary. At the place of diver- 
gence, above the lower palatal layer, are the mid fossa and two lateral nervo-vascular 
canals conveying the trunks of the many ramifications which emerge at the perforations 
of the cork-like outer surface to constitute (or help thereto) the periosteal formative 
bed of the upper horny mandible. 
The maxillary is broadest anteriorly, where it sends inward from its lower park wie 
contribution to the roof of the mouth called “ palatal plate or process of the maxillary, 
answering to the same processes in the Crocodile and in Mammals. ‘The upper plate 
of this fore part of the bone swells into an oblong convex dome, roofing a sinus 
~ id i 
' The homologue of the ridge bisecting the temporal fossa, and produced beyond the ordinary mastoid in 
Ajtornis (V1, XLITIL, figs. 1, 8'). 

