20 VERTEBRATES 



is much the same in its general character in all verte- 

 brates. This system as it appears in Man, the highest 



vertebrate, is shown 



jj!w.ji|;j a in Fig. 22. Besides 



i inclosing the brain 



^^>^.^^ ^ and spinal cord, the 



"'^--T'^jj. skeleton protects the 



KM^K^^SBRlW organs for breathing 



^"^I^^W VW ^'^'-' digestion, and 



Ab^ supplies the levers 



by which the muscles 

 i^^il^^^l ^^kL move the animal. 



spinal cord are alike 

 in their position and 

 general outlines in 

 all vertebrates, only 

 differing in size and 

 ■^ ^\flSI in degree of perfec- 



^nHl tion, so also are the 



■'™™ skeletons of all ver- 



tebrates alike in their 

 principal features. 

 The backbone of one, 

 in its position and 



f XT . c.u u- 1 . general outlines, cor- 



Fig. 22. — Nervous system of the highest >= ' 



Vertebrate — Man. responds to that of 



,1, principal brain, called the hemispheres; /-, all the OtlierS \ SO 

 smaller brain: c- spinal cord giving off its branches -.i .i i i „j 



,„„ „ ' ^ '^ With the head and 



ot nerves. 



limbs. The arm of 

 Man, the arm of a Monkey, the wing of a Bat, the leg 

 of a Mole, the leg of a Dog, the paddle of a Seal, the 

 leg of a Sheep, the paddle of a Whale, the wing of a 



