THE FOOT IN GENERAL. 153 



tarsus, metatarsus, and phalanges ,- and, in the archetype, each section comprises 

 five parallel rows, each of which has two tarsal bones, one metatarsal, and three 

 phalangeal. In the present fauna there is not, perhaps, a Mammal which has 

 a perfectly typical pentadactylous abominal limb ; for this ideal disposition is 

 modified in the sense already indicated for the hand. In the following- brief 

 paragraphs, an attempt will be made to show the manner in which Man and the 

 domestic animals may be allotted to the archetype. 



1. 31 an. — In Man the archetype is realized in the metatarsal and phalangeal 

 sections, and it will now suttice to examine the tarsal section. This contains 

 seven separate bones — three in the upper and four in the lower row. It must 

 not be forgotten that the scaphoid, although situated between the two rows, 

 nevertheless belongs to the upper, as happens in the carpus of certain species. 

 Apparently, it is deficient in two bones in the upper row and one in the inferior. 

 This deficiency arises from fusion of the apex of the calcaneum {first superior 

 metatarsal hone) with the remainder of the bone {second hone), of the scaphoid 

 with the fifth hone in the upper row, and of the first inferior tarsal bone with the 

 cuboid in the second row. 



2. Carnivora. — The foot of Carnivora only differs from that of Man in the 

 arrangement of the thumb ; as this digit has usually no phalanges, and its meta- 

 tarsal piece is only a small, very short styliform bone. Notwithstanding this 

 difference, the pentadactylous archetype is as easily recognized in the foot of 

 these animals as in that of Man. 



3. Rodents. — The foot of the Rahhit and Hare is yet less complete than that 

 of Carnivora, as the metatarsal of the thumb is absent ; but, by the constitution 

 of the tarsus, Rodents resemble Carnivora and Man, and consequently they can 

 be also classed in the pentadactylous type. 



4. Pig. — In this animal, the tarsus presents the same number of pieces and 

 the same fusions, as in Rodents, Carnivora, and Man. The metatarsus and 

 phalangeal section have four complete toes — first, second, third, and fourth ; 

 and with regard to the fifth digit, it is represented by a short, flat, and irregu- 

 larly triangular metatarsal, articulating posteriorly with the third metatarsal, and 

 attached to the third cuneiform by some ligamentous fibres. 



5. Ruminants. — The foot of the Ox, Sheep, and Goat present numerous 

 fusions, and even some abortions. The tarsus has only five distinct bones ; for, 

 besides the fusions which exist as in the preceding animals, the scaphoid is united 

 to the cuboid, and the third cuneiform is completely aborted. 



The metatarsus of these animals includes a principal metatarsal, provided, 

 inferiorly, with a double diarthrodial surface, and an internal rudimentary 

 metatarsal. Must we consider the principal metatarsal as the result of the fusion 

 of the third and fourth, and admit, in Ruminants, the abortion of the first two 

 digits ? Several anatomists have professed this opinion. Lavocat did so at first, 

 and then abandoned it. He considered the principal metatarsal as due to fusion 

 of the metatarsals of the first four digits, and he expressed himself on this point 

 as follows : " The first and the fourth metatarsals are visible, and fused above 

 and behind the united large metatarsals. Each of them has the shape of a thick 

 pyramid, with its base uppermost, large, and about five centimetres long in the 

 Ox. Above, they join to form an arch, which is the contour of a wide and short 

 vascular canal running between them and the two large metatarsals, and which 

 does not exist in the Goat and SheejJ. Their widened superior extremity is in 

 contact with the bones of the tarsus, to wit : the first metatarsal with a facet of 



