32S COMPARATIVE ZOOLOGY. 
New Zealand (. Di~ 
nornis , or Moa). 
This singular ge¬ 
ographical distri¬ 
bution, like that 
of the Dipnoi and 
Marsupials, shows 
that the group was 
once widel y spread 
over the earth, but 
is now greatly re¬ 
stricted in area. 
Subclass II. 
Carinatae. 
Birds with a 
keeled sternum, 
and with devel- 
A . Aquatic Birds. —Specially organized for swimming; 
the body flattened, and cov¬ 
ered with water-proof cloth¬ 
ing—feathers and down ; the 
legs short (the knees being 
wholly withdrawn within the 
skin of the body), and set far 
apart and far back; the feet 
webbed,and hind-toe elevated 
or absent. The legs are al¬ 
ways feathered to the heel at 
least. They are the only Birds 
whose neck is sometimes 
longer than the legs. 
1. Pygopodes, or Divers.— 
These lowest of the feathered 
