Art. XIX.—Notes on Three Moa-skulls, probably referable to the Genus Pachyornis.

Transactions and Proceedings of the Royal Society of New Zealand, Volume 26, 1893, Page 223

Art. XIX.—Notes on Three Moa-skulls, probably referable to the Genus Pachyornis. By Professor T. Jeffery Parker, D.Sc., F.R.S. [Read before the Otago Institute, 14th November, 1893.] In the collection of moa-bones recently made at Enfield, near Oamaru, by Mr. J. Flett, there are three skulls of special

interest, which have been handed to me for identification by Mr. A. Hamilton. As I am unable to refer them with certainty to any of the hitherto described species, I append a brief description of each, with measurements. The terminology and the system of measurement employed are those used in my paper “On the Cranial Osteology, Classification, and Phylogeny of the Dinornithidæ,” now in course of publication in the Transactions of the Zoological Society of London.*See Proc. Zool. Soc., 14th February, 1993. Skull No. 1.—This is undoubtedly a skull of some species of Pachyornis, differing from P. elephantopus mainly in its greater size. It has the characteristic vaulted skull, wide squamosal region, prominent mammillar tuberosities, widely-separated optic foramina, large temporal fossæ, narrow, pointed beak, and stout, boldly-curved, maxillo-jugal arch. The supra-occipital region is very prominent, and the posterior lambdoidal ridge strongly curved backwards. It is about 10 per cent. larger in nearly all dimensions than P. elephantopus, from which I have little doubt that it is specifically distinct. As P. immanis, Lyd., at present known only by leg-bones, differs from P. elephantopus in its greater dimensions, I think the present specimen may be referred provisionally to that species. The whole frontal region is marked with shallow feather-pits, and a somewhat rhomboidal area forming the roof of the posterior olfactory region is strongly marked with irregular, probably venous, depressions, which, as Mr. Hamilton suggests, may possibly indicate the possession of a caruncle by this species. Skull No. 2.—This specimen consists of the cranium only. It has the general characters of Pachyornis, but is about 10 per cent. smaller in nearly all dimensions, and is further remarkable for the fact that the wide temporal fossæ are hardly produced on to the roof of the skull, so that what I have called the temporal index (see below) is only about 100:104, instead of 100:130–140, as in P. elephantopus. In this respect, therefore, the skull resembles that of Emeus, but the great width of the temporal fossa, the prominent mammillar tuberosities, and the distance between the optic foramina, incline me to place it under Pachyornis. Unfortunately, the premaxilla, maxillo-jugal arch, and mandible are absent, and without them it is impossible to determine the genus with certainty. I propose to call it provisionally Pachyornis, species β. Skull No. 3.—In this case also the cranium alone is present, and, as will be seen from the table of measurements, is

smaller in most dimensions than No. 2, just described. It is a typical Pachyornis, having the large temporal fossæ continued well on to the roof of the skull, as well as the general contour characteristic of that genus. The distance between the optic foramina is, however, not more than half of what is usual in Pachyornis, and agrees with what is found in Emeus and Anomalopteryx. I propose to give this specimen the provisional name of Pachyornis, species γ. Table of Absolute Measurements, in Millimetres. — Pach. elephantopus. Pach. immanis(?). Pach., sp. β Pach., sp. γ Length of cranial roof 98 110 91 91 Length of basis cranii 40 47 35 35 Width across paroccipital processes 78 73 66 59 Width across squamosal prominences 92 96 82 76 Width across temporal fossæ 57 59 51 46 Distance between temporal ridges 44 44 49 31 Height 55 61 49 43 Width of temporal fossæ 32 30 29 27 Distance between optic foramina 21 24 22(?) 11(?) Width of orbit 32 36 30 28 Table of Proportional Measurements. Length of basis cranii 100 100 100 100 Length of cranial roof 234–245 234 260 260 Width across paroccipital processes 151–195 155 188 168 Width across squamosal prominences 208–218 204 234 217 Width of temporal fossa 70–80 80 82 77 Temporal Index. Distance between right and left temporal ridges 100 100 100 100 Width of cranium at temporal fossæ 130–140 134 104 148