316 



Genus PACHYORNIS, Lydekker (gen. nov.). 

 Syn. Palnpteryx, Haast ' (non Owen, typically). 



The skull is either vaulted or flattened, with a sharp and narrow 

 beak^, and shorter and more rounded paroccipital processes, and 

 more prominent basioccipital tubercles than in Anomalopterya-, the 

 quadrate and mandible closely resembling those of that genus. 



Fig. 64. 



Pachyornis clcphantopus. — Sternum. \. a, costal process ; b, lateral process. 



The sternum (fig. 64) is flat, and very broad and short, with no 

 coracoidal facets, a very small xiphisternal notch, broad and short 

 costal processes, broad and widely divergent lateral processes, and 

 only two costal articulations. The pelvis is extremely low and 

 wide, with the anterior wall of the acetabulum very deeply concave, 

 the ventral surface of all the vertebrae behind the true sacrals 

 narrow and convex, and from which the very broad sacral ribs 

 ascend to join the ilium, of which the inferior postacetabular border 

 is very sharp and descends far below the level of the ribs ; there is 

 no pectineal process to the pubis. The tibio-tarsus (fig. 65, B) is 

 very short, with the shaft curved outwards, the distal extremity 

 markedly inflected, the fibular ridge much shorter than in the pre- 

 ceding genera, and the fibular border below the smooth space at 

 the distal extremity of the fibular ridge extremely rough ; the distal 

 extensor tubercle is very prominent, and situated partly on the line 

 of the upper half of the extensor groove, instead of being altogether 

 external to the same. The tarso-metatarsus (fig. 66) is still shorter 

 and wider than in Emeus, the width at the middle of the shaft 

 being usually rather more than one third of the length ; the third 



1 Ibis, ser. 3, vol. iv. p. 212 (1S74). 



- Haast assigned to his Pahtpteryx a broad-beaked skull, but the error is 

 correcLed by Huttou, Traus. N. Zealand Inst. vol. ix, p. 365. 



