The Ostriches consist of two genera, sometimes formed into distinct families. Struthio (2 sp.) inhabits the desert regions of North, East, and South Africa, as well as Arabia and Syria. It therefore just enters the Palæarctic region. Rhea (3 sp.) inhabits Temperate South America, from Patagonia to the confines of Brazil.
Family 127.—CASUARIIDÆ. (2 Genera, 11 Species.)
| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| — — — — | — — — — | — — — — | — — — — | — — — — | 1. 2 — — |
The Cassowaries and Emeus are confined to the Australian region. The Emeus, Dromæus (2 sp.), are found only on the main-land of Australia (Plate XII. Vol. I. p. 441). Casuarius (9 sp.) inhabits the islands from Ceram to New Britain, with one species in North Australia; it is most abundant in the Papuan Islands.
Family 128.—APTERYGIDÆ. (1 Genus, 4 Species.)
| General Distribution. | |||||
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| Neotropical Sub-regions. | Nearctic Sub-regions. | Palæarctic Sub-regions. | Ethiopian Sub-regions. | Oriental Sub-regions. | Australian Sub-regions. |
| — — — — | — — — — | — — — — | — — — — | — — — — | — — — 4 |
The species of Apteryx are entirely confined to the two larger islands of New Zealand. They are supposed to have some remote affinity with Ocydromus, a genus of Rails peculiar to Australia and New Zealand; but they undoubtedly form one of the most remarkable groups of living birds (Plate XIII. Vol. I. p. 445).
Struthious Birds recently extinct.
A number of sub-fossil remains of birds, mostly large and some of gigantic size, having affinities to the Apteryx and, less closely, to the Cassowaries, have been discovered in New Zealand. These are all classed by Professor Owen in the genus Dinornis and family Dinornithidæ; but Dr. Haast, from the study of the rich collections in the Canterbury (New Zealand) Museum, is convinced that they belong to two distinct families and several genera. His arrangement is as follows. (See Ibis, 1874, p. 209).
Family 129.—DINORNITHIDÆ. (2 Genera, 7 Species.)