240 AVES. 



D. giganteus, as yet only imperfectly known ; D. maximus is larger and 

 better known, the tibio-tarsus being nearly a metre in length, and the 

 total height of the bird over 3'5 metres. 



Pachyornis (fig. 144 A). A genus comprising smaller but much 

 stouter species. In the skull the occipital plane is vertical or slightly 

 inclined backwards, and the occipital crest is prominent; the temporal 

 fossae are large. The beak is relatively wide, though pointed. The 

 sternum is short, broad, and flattened, with no coracoidal facettes, only 

 two costal facettes on each side, the lateral processes broad and very 

 widely divergent, and a relatively small xiphisternal notch. The pelvis 

 is remarkably low and broad, and the pectineal process is wanting. The 

 hind limbs are extremely massive, and the tibio-tarsus relatively short. 

 No evidence of a hallux has been observed. The typical species is 

 Pachyornis elephantopus. 



Anomalopteryx. Small birds of comparatively slender build. The 

 skull is narrow and elevated, with a sharply pointed beak; the pneu- 

 matic foramen in the quadrate is small. The sternum is much longer 

 than broad, moderately flattened, with little or no coracoidal facettes, 

 three costal facettes on each side, and a pair of long, slender, lateral 

 processes. The pelvis much resembles that of Pachyornis, but the hind- 

 limbs are not very massive. The tarso-metatarsus is shorter than the 

 femur, and scarcely half as long as the tibio-tarsus. A hallux is pre- 

 sent. The typical species is Anomalopteryx didiformis. A. parva is the 

 smallest known member of the Diuornithidae, the species being founded 

 oil a nearly complete skeleton scarcely a metre in height. 



Other genera commonly recognized among the Dinornithidse 

 of New Zealand, are named Emeus, Megalapteryx, and Meso- 

 pteryx. There is no certain evidence of the occurrence of the 

 family in Australia or elsewhere. 



Sub-Order 5. Megistanes. 



Paleontology adds nothing to our knowledge of the distri- 

 bution of the Emeus and Cassowaries. An extinct emeu (Drom- 

 ornis) is known by fragmentary remains from the superficial 

 deposits of eastern Australia. 



Sub-Order 6. Rhece. 



Remains of the Rheas are likewise known only from the 

 superficial deposits of South America, where these birds still 

 exist. 



