THE BIEDS OF AUSTRALIA. 
In the family Tytonid(B, however, I am compelled to lag behind, as I can 
only recognise two genera for four species, though a third seems suggested. 
I again observe in this connection that Northern genus-lumpers with their 
ratio of nine genera to ten species in the North, range all these four under 
one genus — a most remarkable conclusion. 
It might be useful to reproduce the distinguishing features of these two 
families as given by Sharpe in the Catalogue of the Birds in the British 
Museum, Vol. II. 
The general features of the Order are expressed in this manner : 
“ Outer toe reversible ; eyes directed forward and encircled by a facial 
disk ; nostrils generally hidden by stiff bristles ; plumage soft and fluffy ; 
tibia more than double the length of tarsus.” 
The family Bubonidce ( = Strigidce of this place) is thus diagnosed : 
“ Hinder margin of sternum with two or more distinct fissures or clefts ; 
furcula free, not attached to keel of sternum ; inner margin of claw on middle 
toe not serrated ; middle toe always longer than the inner one.” 
The family Strigidce {=■■ Tytonidce of this place) is then differentiated as 
follows : 
“ Hinder margin of sternum entire, with an emargination but no distinct 
cleft ; furcula joined to keel of sternum ; inner margin of claw on middle 
toe serrated ; inner and middle toes about equal in length.” 
It will be interesting to have Australian ornithologists’ observations on 
the value of these characters when applied to Southern Owls. 
With regard to the genesis of Australian Strigiformes, it is not possible 
to indicate much, as superficially they do not give many clues to their origin. 
I have suggested more than one Northern immigration in connection with 
Australian Falconiformes, and it is possible that later, with good anatomical 
knowledge, we may be able to trace some similar migrations in the present 
Order. 
We obseiwe the same scarcity of this group in Tasmania, only two species 
being there established. A peculiar feature in connection may be suggested : 
the Tasmanian forms in each case seem to have retained what may have 
been the earlier state of plumage. This is not certain, but it is strongly 
indicated in the case of Strix novcehollandice, as I will hereafter more fully 
discuss. 
A form of the Barn Owl, a world-wide species, occurs throughout 
Australia but not Tasmania. All the rest of the Owls are Indo-Malayian, 
or more strictly Austral-Papuan, the most specialised being restricted to 
Australia. Thus Spiloglaux occurs in New Zealand and islands as well as in 
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