408 



ANIMAL MECHANICS. 



i°. Man posseses a distinct flexor pollicis longus* which 

 does not occur in any Quadruman. 



2°. Man possesses two distinct extensors of the phalanges of 

 the thumb ; while the Quadrumans possess either one or none. 



3°. In Man the Indicator belongs to the second finger 

 only ; while in the Quadrumans it belongs to the second and 

 third fingers jointly. 



4°. In Man the Auricularis belongs to the fifth finger only ; 

 the Chimpanzee and Ateles resemble Man in this respect ; 

 and in the other Quadrumans, the Auricularis belongs to the 

 fourth and fifth fingers jointly. 



The following Tables show the relative developement of 

 the various muscles and groups of muscles :■ — 



Muscular Types of Man and Quadrumans — Hand. 





Man. 



Gorilla. 



Chim- 

 panzee. 



Haraa- 

 dryas. 



Walking Muscles. 



1. Flexor carpi radialis, . 



2. Flexor carpi ulnaris, . . 



3. Palinaris longus, .... 



Grasping Muscles. 



1. Flexor digitorum sublimis, . 



2. Flexor digitorum profundus, 



3. Flexor pollicis longus, . . 



Extending Muscles. 



1. Extensor carpi radialis (a), . 



2. Extensor carpi radialis (j3), . 



3. Extensor carpi ulnaris, . . 



4. Extensor digitorum longus, . 



6. Extensor assis metacarpi pol- \ 



7. Extensor primi internodii ) 



8. Extensor secundi internodii ) 



Per cent. 



5 4° 

 8.06 

 2.58 



17.71 

 21-53 ) 

 4.24) 



9.65 

 6.48 

 5.65 

 8.3, 

 1. 41 

 4.24 



0. 67 



2.41 

 1.66 



Per cent. 

 7. 17 

 9-73 



0- 75 



18. 92 

 33.25 



2.56 

 5. 12 

 4. 60 

 8.7i 

 2. 04 



4 60 



1- 53 

 1 . 02 



Per cent. 



7-77 

 6 89 

 1.72 



14- 65 

 34.49 



6. 03 

 5. 17 



3- 45 

 9 49 

 1.72 



4- 31 



2 59 

 1.72 



Per cent. 



8.24 

 16.49 



3-59 



12. 02 

 28. 13 



5.01 

 6.08 



5 55 

 6.81 

 1 62 



4.48 



0. 90 

 1.08 





IOO 



IOO 



IOO 



ICO 



Oz. av. 

 5-58 



Oz. av. 



Total weight, . . 12 03 



Oz. av. 

 O 98 



Oz. av. 

 1-16 



* For a remarkable exception to this rule, vide pp. 122-3. 



