204 NEW ZEALAND NATURE-STUDY BOOK 
sense of smell. In past ages it had no need to keep watch 
against birds of prey, and as its eyes were not needed in 
looking for food, there remained little for them to see, 
hence they diminished in size and efficiency to a degree 
elsewhere unknown in the bird class. 
Varieties of Birds. The foregoing deals in some 
detail with a few types of New Zealand birds. It might 
be found desirable to arrange these and others into certain 
groups noting the points of resemblance and difference. 
Some such arrangement as the following might be adopted 
either as a summary of what has already been done, or as a 
working scheme for lessons on bird life. 
Climbing Birds. Two toes before and two behind, 
upper mandible longer than lower—Parrots and Cuckoos. 
Perching Birds. Slender and relatively short legs ; 
three toes before and one behind—Sparrows, ‘Thrushes, 
Pigeons, Tuis, etc. 
Running Birds. Strong legs, wings small and useless 
for flying—Ostriches, Emus, Kiwis, etc. 
Scratching Birds. Strong legs, often covered with 
feathers, stout horny claws—Common Fowl, Pheasants, ete. 
Wading Birds. Long and generally slender legs, 
bare —Pukekos, Herons, Bitterns, Stilts, ete. 
Swimming Birds. Webbed feet, boat-shaped bodies 
—Ducks, Geese, Swans, Shags, Gulls, ete. 
Raptores or Birds of Prey. Strong curved sharp 
bill, muscular bodies, strong legs, sharp curved claws, 
(talons)—Hawks, Owls, etc. 
Birds of the district. It is hardly necessary to point 
out that, in any scheme of lessons, the birds of the district 
should receive special attention. Indeed it will probably 
be found necessary to confine the work at first to this 
particular part of the subject. Whatever is learnt should be 
