GENERAL CONSIDERATIONS. 



ENUMERATION AND CLASSIFICATION OF THE SPECIES OF DOMESTICATED 



ANIMALS. 



The object of this book is the study of veterinary anatomy. The 

 animals of which it treats belong to the mammiferous class and to that Of 

 birds. 



The domesticated mammals of our regions have their representatives in 

 a large number of orders. Thus, we find among them : 



1. Of the carnivora, the Dog and Gat; 



2. A rodent, the Rabbit ; 



3. A pachyderm, the Pig ; 



4. Of solipeds, the Horse and Ass ; the produce of the male ass with 



the mare, i.e., the Mule, and that of the horse with the female ass, 

 known by the name of Hinny ; 



5. Of ruminants, the Ox, Sheep, and Goat. 



With regard to poultry, they range themselves : 



1. In the gallinaceous order, the genera to which the common fowl, 



guinea fowl, turkey, and pigeon belong ; 



2. In the order of palmipeds, the geese and ducks. 



Girard has proposed a special classification for the domesticated mammals, 

 based upon the number of digits terminating each of their limbs, and has 

 defined four categories : the first comprises the horse, ass, mule, and hinny, 

 which take the name of monodactyles, because their digital region is composed 

 of a single digit ; in the second, under the denomination of didactyles or 

 bisulcate animals, those with two digits, such as the ox, sheep, and goat ; in 

 the third, or regular tetradactyles, is found ranged the pig, each of whose 

 limbs shows four digits ; lastly, the dog and cat, which most frequently 

 have four digits on the posterior members and five on the anterior ones, and 

 form the class of irregular tetradactyles. 



This nomenclature will not be followed here, as it is opposed to the general 

 laws of organisation ; philosophical anatomy has, in fact, demonstrated that 

 there are really no veritable monodactyles, didactyles, etc., all are materially 

 or virtually pentadactyles. It is therefore considered better to keep to the 

 classification established by zoologists, because it prevents confusion in 

 scientific language, which should always be the same for everyone engaged 

 in the study of anatomy. 



The regimen, and habits of the domesticated animals bring about differ- 

 ences in their organisation which appear very great at first sight, though in 

 reality they are not so profound as they seem. 



In order to study the descriptive anatomy of all these animals, we will 

 not pass them in review, one after another, giving for each the description 

 of every organ ; but shall take a type, which will most frequently be 

 the Horse, and briefly compare all the others with it. In the majority of 

 cases, we will describe, without leaving the Horse, all the organs of an 

 apparatus ; afterwards the same organs in the other species will be studied 

 in the same order. In this comparison, the animals will be generally classed 

 according to their domestic value ; though exceptions will be made to the 

 rule which has been instituted by our predecessors, whenever any advantage 

 in point of concision or perspicuity is likely to be obtained. 



