Illustrated Study 



219 



FIG. 400. CHIMPANZEE. (See Fig. 406.) 



Illustrated Study of Vertebrate Skeletons: 

 Taking man's skeleton as complete, which of these 

 seven skeletons is most incomplete ? 



Regarding the fish skeleton as the original verte- 

 brate skeleton, how has it been modified for 

 (i) walking, (2) walking on two legs, (3) flying ? 



Which skeleton is probably a degenerate reversion 

 to original type ? (p. 209.) 



How is the horse specialized for speed ? 

 Do all have tail vertebrae, or vertebrae beyond 

 'the hip bones ? Does each have shoulder blades ? 

 Compare (i) fore limbs, (2) hind limbs, (3) jaws 

 of the seven skeletons. Which has relatively the 



FlG qoo MAN shortest jaws ? Why ? What seems to be the 



typical number of ribs ? limbs ? digits ? 

 Does flipper of a dolphin have same bones as arm of a man ? 

 How many thumbs has chimpanzee ? Which is more specialized, the foot of a 

 man or a chimpanzee ? Is the foot of a man or a chimpanzee better suited for 

 supporting weight ? How does its construction fit it for this ? 



Which has a better hand, a man or a chimpanzee ? What is the difference in 

 their arms ? Does difference in structure correspond to difference in use ? 

 Which of the seven skeletons bears the most complex breastbone ? 

 Which skeleton bears no neck (or cervical) vertebrae ? Which bears only one ? 

 Are all the classes of vertebrates represented in this chart ? (p. 125.) 



