BIRDS. 329 



and edentulous. The anterior limbs are changed into wings, whilst 

 the posterior serve exclusively for standing and running. 



We will, in the first place, treat shortly of the skeleton. The 

 dorsal vertebrae are mostly immoveably connected with each other, 

 sometimes even the bodies of some of them have partially coalesced. 

 The cervical and caudal vertebrae alone admit of motion. The 

 cervical region of the vertebral column is the longest, and often 

 surpasses the whole of the remainder in length. The number of 

 the cervical vertebrae is constantly greater than in mammals, and in 

 reptiles also with the exception of the fossil genus Plesiosaurus ; 

 for there are at least nine, usually between ten and fifteen of them, 

 and in the wading and swimming birds still more (in the swan 

 twenty-three). The first two cervical vertebrae are shorter than 

 the rest; the first has nearly the form of a ring, and receives, in a 

 deep pit, the single articular tubercle of the cranium situated below 

 the great occipital foramen. The rest of the cervical vertebrae have 

 elongated bodies; the perforated transverse processes form a canal 

 through which the vertebral artery and the cervical portion of the 

 sympathetic nerve pass. The anterior branch of this transverse 

 process is prolonged downwards into a stiliform appendage; this 

 part, lying in front of the foramen transversarmm, may be compared 

 with a rib; it is only the posterior part that corresponds to the 

 transverse processes of the dorsal vertebrae. The dorsal vertebrae 

 are provided with moveable ribs. They are much less numerous 

 and also shorter than the cervical vertebrae, hence the dorsal region 

 does not usually form more than a fourth part of the length of 

 the vertebral column, and in birds with a very long neck, as the 

 stork, only about an eighth part. The transverse processes are 

 broad, and at their extremity, on a surface covered with cartilage, 

 receive the tubercles of the ribs. The spinous processes of these 

 vertebrae are long and ridge-like and close upon each other. The 

 anchylosed lumbar and sacral vertebrae form the region of the 

 spinal column which lies between the long ossa mnominata ; they 

 are usually from ten to fourteen in number. Finally, the tail 

 forms the smallest part of the vertebral column, and commonly 



parts of the Zoologie zu seinen Vorlesungen entworfen of this Nestor of modern ana- 

 tomy, which learned work has never been completed. See also the article A ves of 

 OWEN in TODD'S Cyclopaedia of Anatomy and PJiysiol. i. 1836, pp. 264 358. 



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