237 



Sub- Order 2. jEpyornithes. 



The palaeontology of the ordinary Ratite birds is chiefly of 

 interest as demonstrating the much wider geographical range 

 of the order in late Tertiary times than at present. It also 

 reveals certain extinct genera, which can scarcely be claimed 

 as more primitive than their modern representatives but add 

 considerably to the known modifications of which the Ratitse 

 are capable. Among the most important of these may be 

 mentioned the ^EPYORNITHES, of which the bones and egg- 

 shells occur abundantly in the superficial deposits of Madagascar. 

 These birds are as yet only imperfectly known, but seem to be 

 most closely related to Apteryx and the extinct Dinornithidae 

 of New Zealand. 



In this, the typical genus, the skull is relatively small, as 

 usual in the Ratitse, and the single-headed quadrate has been observed. 

 The large basipterygoid processes are especially conspicuous, and there is 

 an open eustachian groove (as in Dinornis). A number of large pits on 

 the top of the skull seem to indicate an enlarged frontal crest of feathers. 

 The sternum is remarkably short and wide, much like that of Apteryx. 

 The grooves for the reception of the coracoids are well developed. The 

 coracoid and scapula are fused together, and resemble those of Casuarius 

 more than those of any other known genus. There is a distinct glenoid 

 cavity for the humerus, which is short and much reduced. The remainder 

 of the wing is not definitely known ; but it is very probable that a termi- 

 nal bone represents the radius, ulna, and maims fused together. The leg- 

 bones are very massive. The fernur exhibits pneumatic foramina, and the 

 tibio-tarsus is destitute of a bony bridge over the groove for the extensor 

 tendons. There is no iutercondylar tuberosity in the tarso-metatarsus. 

 There are four digits in the pes, except possibly in rare instances, where 

 the hallux may be absent. jEpyornis maximus, the type species, is of 

 gigantic dimensions ; but &. titan is still larger, the length of the femur 

 being 0'415 m., that of the tibio-tarsus no less than 0'8 m. 



Mulleromis comprises smaller birds of slighter build, with 

 the frontal bones raised into a small prominence. Their skull 

 is Casuarine in several features. 



Sub-Order 3. Apteryges. 



The Apteryx of New Zealand is not known to have any 

 extinct allies, except closely similar birds represented by 



