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conducted vessels or nerves into the substance of the bone: the middle line of the 
upper surface of the median branch of the premaxillary is impressed by a groove leading, 
also, to a canal which enters the substance of the bone, Where this branch is confluent 
with the body of the premaxillary, it slightly expands towards its anterior end, and a 
deep and narrow groove divides it on each side from the body of the bone. This is 
formed by a strong osseous mass curved downwards, with sharp lateral margins, and richly 
perforated by vascular and nervous foramina. ‘There is a slight median ridge along the 
fore-part of the broad, moderately concave, palatal surface (2b. fig. 3) : and there is a broad 
shallow channel along each side of the same surface, with numerous large foramina 
opening into it, The outer border of this groove is sharply defined. Only the anterior 
border of the naso-palatine foramen is here preserved ; a canal is continued forwards 
from it into the substance of the bone. The apex of the massive, broad, deflected pre- 
maxillary seems to have been rather obtuse. 
The chief difference which the skull under consideration presents as compared with 
that figured in Pl. XLV., is the greater relative extent of the osseous body of the 
premaxillary, and of its downward curvature, in which it resembles in the same degree 
the skull presumed to be of the Dinornis figured in Pl. XLIIL. 
From the remarkable modifications of the back part of the cranial portion of that. 
skull, its generic distinction from the large skull under consideration is evident ; and 
if we refer the present large cranium to the genus Dinornis, distinguished as it is by its 
superior extent and curvature of the bony beak from the skull referred to Palapteryz, 
then the still more remarkable skull figured in Pl. XLIII. might possibly belong to the 
genus Aptornis, of which the equally remarkable bones of the legs have been described 
and figured in a preceding Memoir (p. 185). It seems, however, to be too large for 
those small metatarsi. 
The skull of, perhaps, a larger species than the subject of the previous description, is 
indicated by the hinder half of the cranium (Pl. LIII. figs. 1, 2 & 3), which, by the 
persistency of the sutures, the absence of the superoccipital and temporal ridges, and 
the smooth exterior of the bones, has belonged to a young individual of, it may be, the 
Dinornis giganteus. The occipital condyle (ib. fig. 2,1) is larger than in the older skull ; 
the elements of the occipital bone have coalesced: but the lambdoidal suture dividing 
the superoccipital (3) from the parietals (7), the sagittal suture (s), and that dividing the 
parictals (7) from the mastoids (s), and both these from the alisphenoids, remain, Not 
any of these sutures are dentated ; they are more properly ‘ harmonix’: the sagittal is 
the most irreguiar or wavy. The particular form of the cranial bones of the Dinornis is 
indicated by these sutures. 
The superoccipital (3), as in the skull last described, deviates most, by its great breadth 
and small height, from that in other birds: the middle and major part of its anterior 
margin is slightly convex, or subangular forwards, the outer parts notched for the recep- 
tion of the posterior external angles of the parietals: yet, notwithstanding the little 


