360 PROFESSOR OWEN ON THE GENUS PALAPTERYX. 



verse depression nearer the supraoccipital ridge, and the cerehral convexities are less 

 marked than in Dinornis casuarinus. The cranium of the Pal. dromio'ides figured in the 

 former Memoir may have belonged to a younger individual, but the articular depressions 

 at the fore-part of the frontals for the nasals show that the cranial extremities of those 

 bones did not converge and approximate each other, as the corresponding extremities 

 do which have coalesced with the frontal in the Dinornis casuarinus. The olfactory 

 chambers also extend in Pal. dromio'ides, as in Pal. strutho'ides, further back between 

 the orbits, and are absolutely larger than in the Dinornis casuarinus. In the Pal. dro- 

 mio'ides, as in the larger cranium in pi. 38. loc. cit., there is but one large deep oblong 

 articular cavity for the tympanic, instead of the two small subcircular cups as in the 

 Dinornis casuarinus, involving therefore a corresponding difference in the tympanic 

 bone, which must have presented a single proximal condyle as in the Ostrich and 

 Emeu, instead of a double one as in the Dinornis casuarinus. This indicates the larger 

 cranium (tom. cit. pi. 38. figs. 1 — 4) to belong to the same genus as the smaller one 

 (pi. 39. figs. 4 — 6), viz. Palapteryx, and I propose therefore, with regard to the crania 

 of the great birds from the soil of New Zealand, to restrict at present the terra Dinornis 

 to those which agree in generic characters with that here referred to Dinornis casuarinus. 



Cranial characters of the genus Palapteryx. 



A less-mutilated cranium of a Palapteryx (PI. LV. figs. 1 — 3), transmitted by the 

 Rev. William Cotton, M.A., from Wairoa in the North Island, of equal size with that 

 referred to Pal. dromio'ides (pi. 39. fig. 5), but with larger (broader) olfactory cham- 

 bers, smaller orbits, and a more contracted occipital foramen, shows the same minor 

 development of the basioccipital (i') and basisphenoid (5) downwards in comparison with 

 that in Dinornis proper ; the same higher position and independence of the precondyloid 

 foramina (p), the same large and single oblong tympanic articular cavity (?/, fig. 3. PI. LV.) 

 beneath the mastoid, and the same suppression of the broad lower paroccipital ridges. 

 The under surface of the basisphenoid in this specimen is entire, and forms a square 

 horizontal platform (5. fig. 3) ; the posterior angles consisting of hemispheroid protube- 

 rances (1"), and the anterior ones of short thick ' pterygoid ' processes (s'), which are 

 wanting in the skull referred to Dinornis casuarinus. The carotid canals (c) groove the 

 sides of this platform, before they penetrate it. The temporal (6, figs. 1 & 3) and occipital 

 (3) depressions are not so close to one another ; are not divided by a mere ridge as in 

 Pal. dromio'ides, but by a flat tract, as in Pal. strutho'ides ; and the fore-part of the 

 frontals thin off to an edge, which is not notched for the nasals, as in Pal. dromio'ides ; 

 but this latter may be a difference due to the age of the individual. 



In a specimen of a mutilated cranium (PI. LV. figs. 4 & 5), also sent to me by the Rev. 

 WiUiam Cotton, M.A., from the North Island of New Zealand, which equals in size that 



