6 THE DISEASES OP THE DOG. 



tained and slow exertion. We find (for instance) none of 

 those remarkable fibrous arrangements by which the 

 horse is enabled to sleep standing and to thoroughly rest 

 himself without lying down. The digestive apparatus is 

 relatively much less bulky, especially the dental and 

 intestinal portions. The molar teeth being small and 

 short-fanged the skull requires neither large sinuses nor 

 bulky jaws, hence it is light, and only a very small liga- 

 mentum nuchas is required, with which again is asso- 

 ciated the absence of long anterior dorsal spines, such as 

 constitute " withers." The flesh food is easily digestible, 

 and so the main operations of the process are carried on 

 in the stomach, which is large, while the bowels are short, 

 straight, and small ; consequently the total bulk of abdo- 

 minal contents is small, and so the belly has but little 

 superficial abdominal fascia to support its viscera. Vigo- 

 rous and active movements entail a well- developed 

 nervous and circulatory system, and from this result also 

 well- developed kidneys, liver, and lungs ; the latter 

 being associated with wide air-passages, and a remarkably 

 elastic and capacious chest, which narrows anteriorly to 

 allow free play to the fore limbs. These latter are some- 

 what prehensile as well as adapted for locomotive 

 purposes. Thus, there is a small clavicle, the ulna is very 

 well developed and freely rotatory on the radius, and 

 there are five digits armed with claws and each more or 

 less endowed with special muscles. In the hind limb the 

 arrangements are on very much the same pattern, but the 

 power of rotation is much more limited, and one digit is 

 atrophied and thrown out of work. All the organs of sense 

 are well developed, as being much required to enable the 

 animal in a state of nature to procure its food, also the 

 emergencies of its life sharpen its faculties, increase its 

 intelligence, and enlarge its brain. As the young are born 

 in a very helpless state and are naturally subjected to many 

 emergencies and vicissitudes dogs are polyparous, the 

 number at a birth varying much. When nature's means 

 of preventing dogs becoming over-numerous (such as 

 the influences of starvation and the predations of more 



