244 SYSTEMATIC SYNOPSIS. — CARINAT.E — PASSERES. 



III. Odontolc^. — Birds with teeth, implanted in grooves. Vertebrae saddle-shaped 



(heterocoelous). Wings rudimentary, wanting metacarpals. Sternum without 

 keel. Tail short. (Typified by the genus Hesperornis, from the Cretaceous of 

 North America. Fig. 15.) 



IV. Eatit.e. — Birds without teeth. Vertebras (some) saddle-shaped. Wings rudi- 



mentary, or at most unfit for flight, with anchylosed metacarpals. Sternum 

 without keel (as in Odontolcce, fig. 15). Tail short. (Embracing the extinct 

 ]\roas, and the living Ostriches, Cassowaries, Emeus, and Kiwis.) 

 V. Carinat.^:. — Birds without teeth. Vertebrae (some) saddle-shaped. Wings devel- 

 oped, with rare exceptions fit for flight, with anchylosed metacarpals. Sternum 

 keeled. Tail short (as to its vertebrae, which are usually pygostyled). (Em- 

 bracing all living birds excepting the Batitcc.) 



AVES CARINAT^: ORDINARY BIRDS. 



The essential characters of this group, which includes all living birds excepting Ostriches 

 and their allies (Ratite or Struthious birds), are absence of teeth, saddle-shai:)ed faces of the 

 best-developed vertebrae, and keeled breast-bone (fig. 56), in combination with perfection of 

 wing-structure in adaptation to aerial (or aquatic) flight. The metacarpals and three meta- 

 tarsals are anchylosed (figs. 27, 34) ; the scapula and coracoid meet at less than a right angle 

 (very rarely more), and the furculum is usually perfect (fig. 59). (In the flightless parrot of 

 New Zealand {Stringops hahroptilus) , the sternal keel is rudimentary.) The caudal vertebrae 

 are few, and the last few (pygostyle, fig. 56) are peculiarly modified to support the tail-feathers 

 in fan-like array. There is normally extensive post-acetabular anchylosis of tlie pelvic bones, 

 which are normally separate there in the other groups (compare figs. .56 and 15). 



The division of Carinate birds has always exercised the judgment and ingenuity of orni- 

 thologists ; no system that has been proposed has been universally adopted. The orders of 

 Carinatce, therefore, are still provisional. But a great assemblage of birds have been ascer- 

 tained to agree (with few exceptions) in possessing a certain combination of characters, upon 

 which may be based the 



Order PASSERES : Insessores, or Perchers Proper. 



The feet are perfectly adapted for grasping by length and low insertion of the hind toe, 

 great power of apposing which to the front toes, and great mobility of which, are secured by 

 separation of its principal muscle (flexor longus hallucis) from that which bends the other toes 

 collectively (flexor profundus digitorum).^ The hind toe is always present, perfectly incum- 

 bent, and never turned forward or even sideways; its claw is as long as, or longer than, the 

 claw of the middle toe. The feet are never zygodactyl, or syndactyl, or semipalmate, or 

 palmate ; the front toes are usually immovably joined to each other at base, for a part, or the 

 whole, of the basal joints. No one of the front toes is ever versatile. The joints of the toes 

 are always 2, .3, 4, 5, counting from 1st (hind one) to 4th (outer front one). The toes are 

 always 4 in number (excepting Cholornis with 4th toe abortive). (Figs. 36, 37, 42, 43.) 

 Various as are the shapes of the wings, these members agree in having the great row of coverts 

 not more than half as long as the secondaries ; the developed primaries either 9 or 10 in num- 

 ber, and the secondaries more than 6. (Fig. 30.) The tail, extremely variable in shape, has 



1 The notable exception to this statement is the Broadbill family, Eurr/l(smidce, which have a plantar vinculum ; 

 for which reason some authors make them a prime division of Passeres under the name of Desmodactyli, all other Pas- 

 seres being then called Eleidherodaclyli. 



