EVEROD Ue rion: 
THE system of classification followed in the present Classifi- 
volume is that which was set forth by Mr. P. L. Sclater 4°" 
in the ‘Ibis’ for 1880, and which has since been adopted 
by many ornithologists. 
- This scheme commences with the PASSERES, the most 
highly specialised of birds, and ends with the TURBINARES, 
which exhibit the nearest affinities to reptiles. 
In the selection for treatment of those Orders which 
include chiefly birds of aquatic habits, it seems inadvisable, 
from a systematic standpoint, to omit the few species which 
happen to resort to dry situations. Thus from the Order 
GRALLZA the Bustards are not excluded; furthermore, 
considering the affinities of these birds with the LIMICOLA, 
—an Order consisting almost entirely of birds structurally 
adapted for a more or less aquatic life—their admission 
to the text would appear all the more desirable. But on 
the other hand the Order PASSERES, mainly composed of 
land-birds, is excluded, although it contains species such 
as the Dipper, Sedge-Warbler, and others, which live by 
streams and marshes. 
The Cormorants and the Gannet (STEGANOPODES) 
occupy the opening pages; next follow the Herons and their 
allies (HERODIONES), the Flamingoes (ODONTOGLOSSA:), 
and the Geese, Swans, and Ducks (ANSERES). 
Passing over three Orders of land-birds (COLUMBA, 
PTEROCLETES, and GALLINA), next come the Rails, 
Cranes, and Bustards (GRALLA), the Plovers, Snipes, 
Sandpipers, Curlews, and their allies (LIMICOLA‘), the 
Terns, Gulls, and Skuas (GAVIA), the Auks (ALCAS), the 
Divers and Grebes (PYGOPODES), and lastly the Petrels, 
Shearwaters, Fulmars, and Albatrosses (TURBINARES). 
It will be seen, therefore, that the present work deals 
not only with the widely-separated Orders of web-footed 
birds, but also with wading-birds, many of which latter 
take freely to the water, and often wade so deeply as to 
be carried off their feet, when they will frequently swim for 
a certain distance, while some such as the Water-hen, the 
