THE BIRDS OF AUSTRALIA. 
it is composed of fourteen feathers. Phylogenetically this would represent 
the oldest form, the aforementioned genera showing specialisation in two 
extreme ways. 
The last Family, Pelecanidm, again utilised generically by Ogilvie-Grant 
in a Brissonian manner, though Brisson named it Onocrotalus, not Pelecanus, 
must be divided into several genera. The single Australian species is verv 
well differentiated, being one of the largest Pelecans known, agreeing in size 
with the typical member of the genus Pelecanus, but separated from every 
other Pelecan by the feathered lores. Inasmuch as Pelecans vary in size and 
coloration immensely in various parts of the world and are a very ancient 
form, this apparently small item becomes a very important character when 
these birds are considered from a phylogenetic standpoint. 
This Order, then, shows a great deal of peculiarity in manner and is 
worthy of the closest study in every way ; series, showing plumage 
evolution, are desirable and also series showing structural evolution should 
be studied. 
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