ANIMAL MECHANICS. 



113 



Phalanger {long flexors of toes). 

 Flexor dig. long., . . . 100 



1. Second toe, .... 5.9 per cent. 



2. Third toe, 5.9 „ 



3. Fourth toe, .... 29.4 „ 



4. Fifth toe, ..... 29.4 



5. Deficiency, 29. 4 „ 



Total, . . 100.0 



(/.) The Birds. — The arrangement of the long flexor ten- 

 dons is very similar in all birds, and the tendons are so long, 

 that the question of the amount of force lost by friction in 

 their passage round the heel possesses great interest. 



The fl. dig. long, and fl. hall. long, muscles are distinct, and 

 their tendons generally unite before reaching the heel. 



1. Ostrich (long flexor tendons of toes). 



1. Outer toe, 7.1 percent. 



%. Inner toe, ..... 92.9 



100.0 



Weight. 



1. Flexor dig. long., . . 49.7 per cent. . 5.90 oz. av. 



2. Flexor hall, long., . . 25.7 „ . 2.08 ,, 



3. Friction, 24.6 ,, 



Total, . . 100.0 



In the Ostrich, as in the other StruthionidaB, the tendons 

 of the fl. hall, longus and fl. dig. longus unite into a common 

 tendon, at a point half way down the cannon bone. 

 I 



