378 THE ANATOMY OF VERTEBEATED ANIMALS. 



more tlian one pair of incisors, and that the outermost, in 

 the upper jaw of the adult. Canines may or may not exist 

 in the upper jaw; they are always present in the lower 

 jaw, and are generally inclined forwards and closely 

 approximated to the incisors, which they usually resemble 

 in form. It consequently happens that they are often 

 reckoned as incisors, and Ruminants are said to possess 

 eight cutting teeth in the lower jaw. 



With one exception (Sycemoschus), the metacarpal and me- 

 tatarsal bones of the third and fourth digits early become 

 ankylosed together into a single, so-called, cannon bone. 

 There is a peculiar bone called malleolar, which takes the 

 place of the distal end of the fibula, articulating below 

 with the calcaneum and above with the astragalus. 



The great majority of the E-uminantia possess horns, the 

 bony supports, or cores, of which are developed on each 

 side of the middle line; and, except in the Giraffe, are 

 outgrowths of the frontal bones. 



The stomach has, at fewest, three divisions ; and, in the 

 majority of the B/mninantia, it has four compartments. 



If the stomach of a typical Ruminant, such as a Sheep or 

 an Ox, be examined, it will be found to be divisible into two 

 principal moieties, the one cardiac and the other pyloric, 

 while each of these is again subdivided into two others. 

 Thus the extreme cardiac end of the cardiac moiety is 

 dilated into an enormous sac of in-egular form, the miicous 

 membrane of which is raised up into a vast number of close- 

 set papillae. This chamber is the JRwmen, or Paunch. It 

 communicates, by a wide aperttu-e, with a much smaller 

 chamber, which constitiites the second sub-division of the 

 cardiac moiety. This is called the Reticulwrn, or Honeycomb 

 stomach, from the fact that its mucous membrane is raised 

 up into a great number of folds, which cross one another 

 at right angles, and, in this way, inclose a multitude of 

 hexagonal-sided cells. The reticulum communicates by a 

 naiTOw aperture with the first subdivision of the pyloric 

 moiety, which is somewhat more elongated in form. The 

 mucous membrane of this subdivision is produced into a 



