

AVES 271 



less united; there are never more than two free digits with 

 claws, and usually none. Four orders of fossil birds are 

 placed in this subclass, as are seventeen whose representa- 

 tives live today. Space will not permit the discussion of 

 all these; they will, therefore, as a matter of convenience 

 be divided into three groups: (1) primitive fossil birds^ 

 (2) recent flightless birds; (3) recent flying birds. 2^ ' 



The fossil Neornithes had some very peculiar features: 

 Hesperornis regalis (Fig. 101) was a flightless bird about 

 four feet long, adapted for swimming and diving. It 

 had teeth set in grooves in the jaws; the sternum was with- 

 out a "keel" for the attachment of wing muscles, and the 

 strong hind feet were webbed for swimming. The re- 

 mains of this great diver have been found in the Cretaceous 

 deposits in Kansas. In the same region the remains of 

 other aquatic birds which had keeled sterna and jaws 

 bearing teeth set in sockets have been discovered. 



The elephant-birds (dZpyornis, etc.) and the moas 

 (DiorniSj etc.) probably became extinct within the past 

 five hundred years. The former were great flightless 

 creatures which lived in Madagascar. The eggs of 

 ^Epyornis have occasionally been dug up along the sea- 

 shore; some of them are over thirteen inches long and have 

 a capacity of a couple of gallons. Over twenty species of 

 moas formerly lived in New Zealand. They were unable 

 to fly and possessed enormous hind limbs adapted for 

 running. Some were as small as turkeys, while others 

 stood ten feet in height. Probably the early human in- 

 habitants of New Zealand exterminated these birds, for 

 remains are found in caves and in ancient refuse heaps. 



Xmong recent birds which fly but little or not at all, the 

 kiwis (Apteryx) of New Zealand are the most striking. 

 They are about the size of a hen and have a very long beak^ 

 which they use as a probe in seeking worms underground. 

 The wings are very degenerate, being represented by small 

 bones which do not appear outside of the body; tail feathers 

 are wholly lacking. The penguins (ofder^Jjnpennes) of 



