Zbc Clovcn*Dootcb Hnimale. 



ELEVENTH ORDER: Artiodactyla. 



SPECIALLY comprehensive 

 is the order of the Artio- 

 dactyla or Cloven-hoofed 

 Animals, which includes all 

 hoofed animals which have 

 only two fully developed 

 toes on each foot, or in 

 which these two at least 

 greatly exceed the three 

 other toes in size. The 

 third and fourth toes, cor- 

 responding to the middle 

 and ring-finger in the hu- 

 man hand, are the digits 

 which are especially large and are of equal develop- 

 ment one with the other, while the others are more 

 or less stunted or merely rudimentary. The first toe, 

 corresponding to the human thumb, is entirely want- 

 ing in all Artiodactyla. The bony skeleton is re- 

 markable for the great uniformity existing among 

 all the species in the number of dorsal and lumbar 

 vertebrae which together always amount to nineteen, 

 except in the case of some domestic breeds, and by 

 the absence of the clavicle or collar-bone. If we 

 add further, that the molar teeth or " grinders " sel- 

 dom exhibit internal convolutions of enamel, but 

 have a filling of dental pulp alone, we will have enu- 

 merated all the common peculiar features in the 

 bony structure of the Artiodactyla, not taking into 

 consideration resultant peculiarities of development. 

 In regard to their mode of life all Artiodactyla re- 

 semble each other in that the majority of them are 

 exclusively herbivorous, while the remainder are, to 

 say the least, chiefly vegetable feeders. In all other 

 regards the order shows widely different forms, cor- 

 responding to its abundance of species. 



The Artiodactyla are not indigenous to New Zea- 

 land and the continent of Australia, but are natives 

 of all other countries in which terrestrial mammalia 

 are to be found. Prehistoric fossil Artiodactyla are 

 first met with in Tertiary geological formations and 

 of some families there are many fossil genera nearly 

 related to existing forms. 



The abundance and variety of species of the Ar- 

 tiodactyla render it desirable for convenience in 

 classification to divide the order first into subor- 

 ders. We distinguish two of these : the Many- 

 hoofed, in the individuals of which the second and 

 fifth toes are more or less developed in addition to 

 the two principal toes, and the Ruminants or Two- 

 hoofed, in which the -toes other than those devel- 

 oped into the two hoofs have either entirely or for 

 the greater part disappeared. In the former the 

 metatarsal and metacarpal bones are separate, but 

 jointed together in a manner similar to those of 

 human fingers and toes, but in the Two-hoofed 

 species these bones are fused together, or anky- 

 losed, forming in each foot a solid bone. 



IRuminante or ^wo^lboofeb Hnimals* 



FIRST SUBORDER: Bidactyla. 



The Ruminants, or Two-hoofed animals {Bidactyla), 

 are all closely allied to each other, notwithstand- 

 ing the fact that they exhibit a great variety in their 

 external structure and appearance. They may pos- 

 sess horns or entirely lack those appendages, may 

 be beautiful or ugly, of graceful or clumsy form, 

 and they also show great diversity in size. Speak- 

 ing generally, the following may be enumerated as 

 distinctive features of the animals of this suborder. 

 The neck is long and very mobile, the head broadens 

 considerably across the forehead or frontal region, 

 and is frequently adorned by horns or antlers. The 

 eyes are large, lustrous, and are frequently exceed- 

 ingly beautiful, the erect ears are well shaped, the 

 lips are mobile, often naked and nearly always de- 

 void of whisker hairs or bristles. The tail is usually 

 short, rarely reaching to the ankle-joints. The hair, 

 which is for the greater part short and thicjcset, lies 

 close to the body; but sometimes grows into a mane 

 or tuft on the neck, on the lower part of the under 

 jaw or chin, on the back and at the tip of the tail. 

 The hair is never bristly, and is often of fine texture, 

 woolly and curly, and its color varies very widely in 

 different species. In all species the structure of the 

 skeleton and of the teeth shows great similarity. Of 

 incisors there are from six to eight in the lower, and 

 none, or in rare cases, two in the upper jaw. There 

 are either no canines or only one on each side of both 

 jaws. There are from three to seven molars on each 

 side of the upper and from four to six molars on 

 each side of the lower jaw. The incisors are usually 

 sharp, broad and spade-shaped, but those of the up- 

 per jaw have a shape similar to the incisors of a Dog. 

 The canine teeth of such Ruminants as possess them 

 are conical, and in a few species protrude laterally 

 frbm the mouth. The molars consist of two pairs 

 of crescent-shaped pillars, the surfaces of which 

 exhibit protruding folds or convolutions of enamel. 

 The skull is elongated and tapers toward the ex- 

 tremity of the muzzle; the orbits of the eyes are sep- 

 arated from the temples by a bony bridge formed 

 by the temporal and molar or cheek bones; the brain 

 cavity of the skull is small. In the spinal column 

 the unusually long, narrow mobile cervical or neck- 

 vertebrae attract the anatomist's attention. In all 

 Ruminants, without exception, only two toes, the 

 third and fourth, are perfectly developed. The mouth 

 is characterized by strong labial or lip muscles and 

 numerous papillae or minute excrescences on the 

 inside; the salivary glands are comparatively large; 

 the stomach consists of four, or at least three differ- 

 ent compartments; the paunch, the honeycomb bag, 

 the manyplies and the reed or rennet. The first 

 is in immediate communication with the gullet or 



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