Geology and Natural History. 149 
the tendons, which latter undergo friction at the wrist and other 
Joints of the hand, the force being applied by the muscles to the 
tendon above the wrist, and the resistance being applied at the 
“a iageaa of the tendons below the wrist by the object grasped 
y the hand. 
From the principle of “Least Action in Nature” we are entitled 
Joints of the foot. In this case, therefore, we should expect the 
united strengths of the flexor tendons of the toes to exceed the 
strength of the flexor tendons above the heel. 
n the case of the hand, friction acts against the muscles; in the 
case of the foot, friction aids the muscles. 
have measured the relative strengths of the deep flexor tendons 
of the hand above and below the wrist in several animals, and also 
the relative strengths of the long flexor tendons of the foot above 
and below the ankle in the following manner:— 
enced by the tendons between the two points of section. 
€ following Tables contain the results of my measurements: 
TaBie L. Friction of Long Fleaor Tendons of Toes. (Cross section of toe tendons 
greater than cross section of muscle tendons.) 
rela gtd 
1. P per cent . r cont. 
2. yrenean Mastiff __......... 65°4 | 1 7 Stang ERIE TEs 33 
3 African Lion ...._ 2.2.22... 59°0 | 18. Japanese Bear _...--.------ 31°7 
Common BOS oo ee ee. 57°6 | 19. Virgini Peau 25°9 
4. African Jabiru _..._.__._... 56°8 | 20. Common Llama -.-.-.------ 
5. Prican Hhesa . 5. 2 cs 5241 9 Hadgehow.. 25-0 
. Indian Jackall __.......... 49-2 | 22, African Ostrich ...--..----- 24°6 
8. American Jaguar __.______- 49-2 | 23. Common Otter .-.---------- 19°8 
9 New Zealand Weka Rail _... 47°5 | 24. Man (mean of 5) ..--------- 16°2 
baer Pheasant oo... snack 47-4 | 25. Spider-Monkey -.---------- 12°3 
andl, ee ee 46-0 | 26, Goat --.- --- on a2-- 2-222" he 
te rns Leopard oon sate. 45-5 | 27. One-horned Rhinoceros ----- 
13 Six-banded Armadillo _..__. 44-4 | 28. Negro-Monkey ------------- 80 
1a phree-toed Sloth -.. 2.228. ‘5 | 29. Brahmin Cow -.------------ 68 
15 Black Swan 36°0 | 30, Nemestrine Macaque ------- =. 
se uians Hares 32.5 36°0 | 31. Boomer Kangaroo ...------- 0 
: European WOH oo 0 
