THE BIEDS OF AUSTRALIA. 
Urospizias, Accipiter (subgenus Cooperastiir), Erythrotriorcliis 
and Mega triorchis. 
VIII. Subfamily Thrasaetin^. Genera Morphnus, Harpyopsis and 
Thrasaetus. 
IX. Subfamily Aquilin se. Genera Spizaetus, Limnaetus, Lophotrior- 
chis, Lophoaetus, Neopus, Spiziastur^ Nisaetus, Aquila and 
Uroaetus. 
X. Subfamily Haliaetinae. Genera Tlialassaetus, Haliaetus and 
Polioaetus. 
XI. Subfamily Buteoninse. Genera Archibuteo, Buteo, Antenor, 
Onychotes, Buteola, Rupornis, Butastur, Asturina, Geranoaetus, 
Leucopternis, Urubitinga, Harpyhaliaetus, Heterospizias, 
Buteogallus and Busarellus. 
XII. Subfamily Milvinse. Genera Haliastur, Milvus (subgenus Lophoic- 
tinia), Gypoictinia, Elanoides, Nauclerus, Gampsonyx, 
Elanus, Ictinia, Rostrhamus, Machserirhamphus, Pernis, 
Henicopemis, Regerhinus, Leptodon and Baza. 
XIII. Subfamily Falconinse. Genera Harpagus, Microhierax, Poliohierax, 
* Spiziapteryx, Dissodectes, Harpa, Hieracidea, Tinnunculus 
(subgenus Erythropus), Hypotriorchis, Aesalon, Chicquera 
and Falco (with subgenera Gennaia and Hierofalco). 
Family Pandionidse. Genus Pandion. 
Since Gurney’s time no one has paid much attention to this group as 
a whole, and consequently we have not the advantage of any accurate 
criticism of the above. It is obvious that a worker, such as myself, 
dealing with a few species from a circumscribed locality only, cannot make a 
detailed reconsideration of the preceding, and can only deal with a few 
points. Moreover, such criticism is of a temporary character and may be 
modified at any time by the accession of more material and further study. 
Sharpe, in the Handlist Gen. Sp. Birds, Vol. 1.^ 1899, somewhat 
improved his 1874 classification, although practically rejecting Gurney’s 
scheme. Sharpe’s emendation shows the recognition of three suborders, 
Serpentarii, Accipitres and Pandiones. The second named has two families, 
Vulturidse and Falconidse ; the latter five subfamilies, viz., Polyborin^, 
Accipitrinac, Buteoninse, Gypsetinse and Aquilinse. 
I would now deal with a classification of the Falconiformes founded on 
osteological study which appeared in the Proc. Zool. Soc. (Lond.) 1902, 
pp. 314-316. There Pycraft, after studying the group for some time, 
accepted Suschkin’s classification. The latter had made a speciahstic study 
of the osteology of the group in the same manner as Gurney had studied 
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