THE VERTEBRATA OR VERTEBRATES. 



FIG. 26. 



Skeleton of a Bird. 



cm, cranium; CT, cervical vertebrae ; p, pel vis; sc, scapula; cl, clavicle; cd, corocoid, 

 formerly regarded as the clavicle; st, sternum; h, humerus; u, ulna; r, radius; c, car- 

 pus; me, metacarpus ; ph and th, phalanges, th being the tlnunb; fe, femur; ft, fibula 

 and tibia, more or less united; t, tibia, where the fibiila is no longer seen, or only 

 faintly indicated ; ts, tarsus ; mt, metatarsus more or less consolidated with the tarsus ; 

 ps, phalanges, or bones of the toes. 



form in all the Vertebrates, differing only or mainly in 

 degrees of development and in special characteristics. This 

 system as it exists in the highest vertebrate Man is 

 shown in Fig. 25. 



Below the spinal column before it in erect Man- 

 there is a cavity for the heart, the organs of digestion, 

 and other organs which perform the functions of vegeta- 

 tive life, that is, the functions of nutrition, etc. 



Although, in defining the Vertebrates, it is sufficient, in 

 most cases, to make special reference, as we have now done, 

 to the spinal column and internal skeleton, it must be 



