79 
CHAPTEE V. 
WATER BIRDS. — CRANES AND BUSTARDS I — THE COMMON 
CRANE, GREAT AND LITTLE BUSTARDS, COURSER, AND 
PRATINCOLE. 
BIRDS have by many naturalists been primarily ar- 
ranged in two series, terrestrial and aquatic, and the 
latter, says Macgillivray, who, both in his ' Manual ' and more 
extended * History of British Birds,' adopts this arrange- 
ment, may in like manner be divided into two groups, 
grallatorial or long-legged birds, addicted to wading, and 
natatorial^ or birds that habitually swim. But among the 
waders there are many that seldom, and some that never, 
enter the water ; and among the swimmers some that pro- 
cure their food on land. Birds cannot, therefore, be strictly 
arranged according to their manner of walking or flying, 
any more than according to their food ; but all these cir- 
cumstances, and others taken in connexion with their organ- 
ization, lead to the formation of orders and families, which 
are in themselves more or less natural, that is, contain 
a series of species obviously connected with each other 
more than with other species. Our readers will, therefore, 
not be surprised to find that we have included under the 
head of Water-birds some kinds whose habits do not appear 
to justiJfy such an arrangement, all of which, however, may 
fitly be called either Waders or Swimmers, being long- 
legged birds, or, if short, those which seek their food and 
pass much of their time in the water. 
In this great primary division, then, we include all the 
British species, whether indigenous or migratory, which 
have not already been described in the previous volumes, 
or under the head of Game Birds, with which this volume 
