146 DR. WALTER KIDD ON THE [Jime 17, 



extended position, in marked contrast with the flexed one of the 

 Ungulates. Thus it happens that the extensor siuface of the 

 Carnivore fore-Hmb lies on the gi'ound, the corresponding surface 

 of the Ungulate being in contact with the flexor siuface of the 

 metacarpus. There are occasions when a Carnivore, such as a 

 domestic cat or dog, doubles up its fore-limb and lies as an 

 Ungulate does ; but this is far from the common habit, and the 

 limb being relatively short, the surfaces in contact are not large. 



This predominant habit of the Carnivores brings to pass a close 

 contact of the flexor surface of the radius and ulna of each side 

 with the pectoral region. Passing backwards, we find that the 

 projecting thorax and upper pai't of the abdomen are in contact 

 with the supporting surface, as in the case of the Ungulate. The 

 hinder portion of the Carnivoie shows much the same attitude as 

 the Ungulate, but it is rather less rotated, and frequently the 

 hind-limbs lie extended under the abdomen in the long axis of 

 the trunk. 



(b) It is hardly too much to say that an Ungulate never sits, 

 and that, in the case of the Carnivores, this attitude in rest is 

 only found with any frequency in the short-bodied forms. In 

 illustration of this, one may point out that it is hai-dly to be 

 conceived that a horse, ox, or deer could sit, and that, to take 

 examples among domesticated Canidae, a dachshund comparatively 

 seldom sits, and that a fox-terrier ov pug spends a large pro- 

 portion of its time iir a sitting posture. Such facts are of course 

 explicable on pm^ely mechanical principles. 



As to the {etiology of the difference of attitudes adopted by the 

 Carnivores and Ungulates, the general shape of the different 

 types will to a great extent account for it. The Ungulate forms, 

 generally speaking, have a short body, long legs, very sloping 

 humerus in standing, and a very sti'ong ligamentum nuchee ; 

 whereas the Carnivore forms have a relatively long body and 

 short legs, humerus more nearly vei-tical than that of the 

 Ungulate, and an unimportant ligamentum nuchpe. 



Of these divergent modifications of fonns, I would suggest that 

 the presence of a powerful and efiicient suspensory ligament in 

 long-necked Ungulates, attached to the nem'al spines of the 

 cervical vertebrae, and to the heavy large head, which in many 

 forms bears the additional weight of antlers, is the factor which 

 mainly determines the Ungulate attitude. This ligament of 

 course allows the Ungulate to maintain the level or elevated 

 position of its head without muscular effort — a position which is 

 greatly more adapted to the general shape of the fore-quarter and 

 the " set " of the head of Ungulates than that of the Carnivore, 

 with the under surface of the lower jaw resting on the ground. 

 The ligamentum nuchae of the Ungulate allows the centre of 

 gravity of the hea^y Ungulate fore- end to be thrown further back 

 than is possible with the Carnivore. The effect of the Carnivore's 

 attitude is to produce a forward slide of the fore-end on the 

 extensor surface of the radius and ulna, where the subcutaneous 



