PROFESSOR OWEN ON THE GENUS PALAPTERYX. 363 



round single (rhinencephalic) depression and foramen leading to the perforated and 

 grooved plate are most obvious in the large si)ecimen referred to Pal. struthioides 

 (PI. XXXVIII. fig. 4). In the cranium of the Palapteryx next in size (PI. LV. fig. 5), 

 the olfactory chambers are broader behind than in the present specimen and have not 

 the transverse ridge: the frontal (fig. 6, ii) is broader and flatter between the antorbital 

 processes, and the lachrymal surfaces beneath these lead to foramina which pierce the 

 supraorbital ridge : the temporal depressions (fig. 4, 8, 12) are relatively larger, and are 

 traversed by a subvertical ridge, which is but feebly indicated in PI. LIV. fig. 1 ; which 

 diflerences, with others before pointed out, indicate the specific distinctions of the birds 

 to which these nearly equal-sized crania belonged. The under surface of a large portion 

 of the frontals, with the coalesced upper prefrontal plates of Palapteryx geranotdes 

 (PI. LIII. fig. 7), shows the median longitudinal ridge for the attachment of the falx, a 

 depression on each side (11) indicative of a median longitudinal rising of the cerebral 

 hemisphere, and a second parallel impression (7) indicative of an outer and more general 

 prominence of the hemisphere. 



Two genera of large birds, as distinct from each other as from the Dinornis, are re- 

 presented by portions of the upper and lower jaws, in Mr. Walter Mantell's collection. 

 The beak which accords in size with the cranium of Palapteryx above-described, is 

 indicated by the anterior extremity of the premaxillary (PI. LIV. figs. 1, 2, 3, 5, 22), 

 and by the symphysis and part of both rami of the mandible (figs. 1 sj, 6 & 7). The 

 end of the premaxillary best accords in form and structure with that characteristic 

 part in the large existing Struthionida, by the close approximation of the external bony 

 nostrils (n, fig. I) to its extremity, and by the nasal groove (ng) continued thither 

 from the anterior border of the nostril, on each side. But amongst these it most 

 resembles the Emeu (tom. cit. PI. XXXIX. fig. I) in the slenderness of the nasal pro- 

 cess (22', figs. 1 & 2), in the angle at which it rises from the broad and flat maxillary por- 

 tions (22), and especially in the palatal plate (22") formed by the union of those portions 

 below the nasal process : but the nasal process, in Palapteryx, is broader and apparently 

 shorter than in the Emeu, as it sooner becomes flattened after leaving the maxillary 

 portion. The tip of the premaxillary is partially fractured ; but from the more perfect 

 extremity of the lower jaw (figs. 6 & 7), it seems to have been more obtuse than in the 

 Emeu, and in this respect more like the Ostrich. The under or palatal surface (22", 

 fig. 3) diff-ers from that both of the Ostrich and the Emeu in having a distinct rough 

 multi-perforated alveolar border (s s), broader than in the Dinornis, and grooved along 

 its outer part, but divided by a sUght convex rising or • bead ' from the gentle concavity 

 of the palatal surface, which is divided into two parts by a low narrow median ridge with 

 a linear impression : the outer border of the alveolar tract is as sharp and even as in 

 the Emeu. The anterior border of the palatal aperture of the nostrils shows this to 

 have been much wider than in the Emeu, where it is a mere linear sUt : it is about an 

 mch from the extremity of the premaxillary. A ridge commencing from the upper part 



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