CHAPTEE XI 



THE ORDER CARNIVORA 



THOUGH the existing Carnivora as at present restricted 1 form a 

 very natural and well-defined order among the Mammalia, it is 

 difficult to find any important common diagnostic characters by 

 which they can be absolutely separated ; so that, as in the case of 

 so many other natural groups, it is by the possession of a combina- 

 tion of various characters that they must be distinguished. Thus 

 they are all unguiculate, and never have less than four well-developed 

 toes on each foot, with nails more or less pointed, rarely rudimentary 

 or absent. The pollex and hallux are never opposable to the other 

 digits. They are regularly diphyodont and heterodont, and their 

 teeth are always rooted. 2 Their dentition consists of small pointed 

 incisors, usually three in number, on either side of each jaw, of 

 which the first is always the smallest and the third the largest, the 

 difference being most marked in the upper jaw ; strong conical, 

 pointed, recurved canines ; cheek - teeth variable, but generally, 

 especially in the anterior part of the series, more or less compressed, 

 pointed, and trenchant; if the crowns are flat and tuberculated 

 they are never complex or divided into lobes by deep inflexions of 

 enamel. The condyle of the lower jaw is a transversely placed 

 half - cylinder working in a deep glenoid fossa of corresponding 

 form. The brain varies much in relative size and form, but the 

 hemispheres are never destitute of well-marked convolutions (Fig. 

 23, p. 71). The stomach (Fig. 234) is always simple and pyriform. 

 The caecum is either absent or short and simple (Fig. 235), and 

 the colon is not sacculated, or greatly wider than the small intestine. 

 Vesiculse seminales are never present. Cowper's glands are present 



1 The Ferse of Linnaeus included all the then known species of the modern 

 orders Carnivora, Insectivora, and Marsupialia. 



2 The tusks of the Walrus, altogether so aberrant in its dentition, are partial 

 exceptions to this statement, but in old individuals the pulp-cavity fills up, and 

 they cease to grow. 



