A MANUAL 
OF THE BIRDS OF AUSTRALIA, 
Cuass AVES. 
THREE subclasses are admitted in this class, all of which are represented in the 
Australian Ornis ; these are the Dromzxornithes, the huge flightless forms previously 
known as Ratitee or Paleognathe; the Impennes or Penguins; and the Euornithes, 
or normal flying birds. 
All existing birds are clothed with feathers, have two wings, a tail, two legs 
and a horny-covered beak. In a few cases the wings have degenerated and become 
flightless, only remnants being recognisable, in a few others the wings have become 
specialised into swimming paddles—in the majority they are very noticeable and 
capable of flight. In a few instances the tail has become almost obsolete, and in 
these instances the flying power of the birds is generally lessened ; in others, the tail 
has become extremely lengthened and generally this is associated with greater powers 
of flight. Though two legs are absolutely constant, the number of toes varies, four 
being the general number, three not uncommon, two in one case only, and no reduction 
to one is yet known, nor are five met with in nature. The legs may be so short as 
to be almost useless for walking purposes, or they may be so extremely long as to 
seem disproportionate. The beak shows many modifications in different ways, 
according to the feeding methods of the birds. Birds have been generally classified 
by the variations in these characters, and by means of judicial consideration of all 
these a fair appreciation of the relationships may be attained. When the results 
are checked by means of osteological and anatomical research we may prepare a 
definite system of arrangement with due deference to phylogenetic considerations. 
As all the subclasses are represented, we refer to the detailed figures and descriptions 
given throughout the work for amplification of the items above mentioned. 
Suspctass DROM HORNITHES. 
This subclass is composed, as to recent birds, of three orders: Struthiones, Rhex 
and Casuarii. The former is confined to Africa and the Syrian Desert, the second 
to South America, and the last named to the Papuasia-Australian Region. The 
differences between the orders are so marked that a very close relationship might be 
justifiably denied. As a matter of fact many more differential features can be cited 
than characters proving alliance, and itis now being accepted that these maj represent 
specialised forms. Superficially they are all very large birds with stout bodies, 
long necks and long stout legs, but no wings capable of flight, or distinct tail. 
The order Casuarii only interests us, as to discuss its non-affinity with the others 
would occupy too much space in a work like this. 
OrpvER CASUARII, 
This is coequal with the suborder Casuariiformes which covers two families, 
Dromiceiide and Casuariide. These are superficially easily distinguished by the 
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