1856] and the Aboriginal Cattle of Britain. 257 



sacrum, viz., 13 dorsal, and 6 lumbar. The palaeotherium had 16 

 dorsal, and 7 lumbar vertebrae. 



The anoplotherium had a femur with 2 trochanters, and the 

 fore-part of the ankle-bone, called "astragalus," divided in 2 

 equal facets. Its hoofs formed a symmetrical pair on each foot. 

 Cuvier has very justly inferred that its stomach must have been 

 complex, and probably, in some respects, like that of the camel or 

 peccari. The palaeotheriiun had a femur with 3 trochanters, an 

 astragalus with its fore-part unequally divided, and hoofs, 3 in 

 number, on each foot. It most probably had a simple stomach, 

 like the tapir and rhinoceros, which, amongst existing animals, most 

 nearly resemble that extinct primitive hoofed quadruped, with 

 toes in uneven number. 



Every species of ungulate mammal with an uneven number of 

 hoofs or toes, that has been introduced into this planet since the 

 eocene tertiary period, whether it have 1 hoof on each foot, as in 

 the horse, 3 as in the rhinoceros, or 5 as in the elephant, resem- 

 bles the palaeotherium ^in having more than 19 dorso-lumbar ver- 

 tebrae, which vertebrae also differ in number in diflferent genera ; 

 22^ e.g. in the rhinoceros, 23 in the mastodon, 27 in the hyrax. The 

 typical pachyderms, with an odd number of hoofs, have also three 

 trochanters on the femur, 'the fore-part of the astragalus unequally 

 divided, and the pattern of the grinding surface of the molar teeth 

 unsymmetrical, and usually crossed by oblique enamel ridges. All 

 the existing odd-toed or perissodactyle mammals have a simple 

 stomach, and a vast and complex caecum ; the horned species have 

 either a single horn, or two odd horns, one behind the other on the 

 middle line of the head, as, e.g., in the one-horned and two horned 

 rhinoceroses. 



Every species of ungulate animal with hoofs in even number, 

 whether 2 on each foot, as in the giraffe and camel, or 4 on each 

 foot, as in the hippopotamus, resembles the anoplotherium in having 

 19 dorso-lumbar vertebrae, neither more nor less ; in having 2 

 trochanters on the femur, in having the fore-part of the astragalus 

 equally divided, and in having the pattern of the grinding surface 

 of the molar teeth more or less symmetrical. The homed species 

 have the horns in 1 pair, or 2 pairs. All have the stomach more 

 or less complex, and the caecum small and simple. In the hog the 

 gastric complexity is least displayed ; but in the peccari the stomach 

 has 3 compartments ; and in the hippopotamus it is still more com- 

 plex. But the most complex and peculiar form of stomach is that 

 which enables the animal to " chew the cud," or submit the aliment 

 to a second mastication, characteristic of the large group of even- 

 hoofed Ungulata, called " JRuminantiaJ^ 



These timid quadrupeds have many natural enemies ; and if 

 they had been compelled to submit each mouthful of grass to the 

 full extent of mastication which its digestion requires, before it 

 was swallowed, the grazing ruminant would have been exposed a 



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