154 THE BONES. 



the prototarsus, or first portion of the cuboid ; the fourth metatarsal with all the 

 inferior facet of the tetrofarsus, or second cuneiform. And each of them has, 

 for this eminently normal connection, an articular facet well separated from the 

 diarthrodial surface of the large metatarsals by a large fossa destitute of cartilage. 

 In this way the first four metacarpals are gathered into a single bundle. . . . 

 Lastly, the thumb, or fifth digit, is constantly represented in the foot by a 

 distinct metatarsal bone — at least in the Ox, Goat, and Sheep.'' 



Notwithstanding the reasons on which Lavocat bases his last interpretation 

 as to the metatarsals of the Ox, we prefer adopting the first. In fact, if some 

 wild Ruminants are examined — Deer, for example — there will be found a tarsus 

 identical with that of the Ox, and a principal metatarsal provided with a vascular 

 canal, with two inverted pyramidal expansions ; and, in addition, two styliform 

 bones lying to the outside and the inside of the principal bone of the shank. 

 These bones evidently represent the metatarsals of the second and fifth digits ; 

 as they exist at the same time as the lateral ridges on the principal metatarsal 

 bone, it appears to be impossible to give to the latter the same signification. 



The posterior phalangeal region of the Ox is almost identical with the an- 

 terior ; it is, therefore, needless to again demonstrate its constitution. That of 

 the Sheq) and Goat has no rudimentary phalanges to serve as a base for the 

 ergot, in the hand ; but the two ergots suffice to represent the first and fourth 

 digits, and so to include these animals in the pentadactylous type. 



6. SoUpeds. — The tarsus of these animals has six or seven bones. In the 

 second case, it is identical with that of Carnivora and Man ; in the first, the 

 second and third cuneiforms are fused. The metatarsus and posterior phalangeal 

 section having the same constitution as those of the anterior, the reader is 

 referred to the description of the Hand in General. 



Article VIII. — The Limbs in General and their Parallelism. 



A. The Limbs in General. — The bony sections which compose the limbs, 

 are destined not only to support the trunk in a stationary attitude, but also to 

 transport it during progression. This double use gives rise to a difference 

 between the anterior and the posterior members. The front limbs, being nearer 

 the centre of gravity than those behind, have to sustain the largest share of the 

 weight. They ought, consequently, to be specially organized as organs of sup- 

 port. Therefore it is, that the four principal bones composing each of them — 

 shoulder, arm, forearm, foot — although flexed, or disposed to be flexed, in an 

 inverse sense to one another, oppose to the pressure of the weight of the trunk — 

 which tends incessantly to throw them down — obstacles purely mechanical, and 

 of such energy that we may still understand how the body can be sustained on 

 the anterior limbs, if we suppose all the muscular masses surrounding these bony 

 columns to be removed, except one. 



Thus, the weight of the body is transmitted to the scapula through the 

 muscles that attach that bone to the trunk. It then passes to the humerus, and 

 thence to the radius, to be thrown, finally, on the different pieces composing 

 the foot. Now, the humerus forming with the scapula an angle which is open 

 behind, and with the bones of the forearm another angle open in front, the 

 weight of the body pressing continually on these angles tends to close them, 

 and thus cause the flexion of these bones. But this result is prevented by the 

 combined action of two muscular powers — the biceps and the extensors of the 



