741 



FELID.F. 



KKLID.S. 



pemuuieot lauiary (canine tooth, or cusnidatii*) is pretty completely 

 formed, and the fang forming. The laniary is cut down in the 

 direction of it* axis to expose the cavity containing the pulp on 

 which it waa forming. There is one of the molars in the act of 

 being abed, and the adult or permanent tooth is pushing into the 

 gum. No. 331 is the counterpart, or oposite section of the same 

 laniary ; and No. 832 is the laniary of the jaw of the opposite side 

 af the same lion, showing the whole of the pulp on which it was 

 forming. (' Catalogue, Physiological Scries, Gallery,' vol. i.) 



Teeth of the Cat Family. 1, upper jw ; a, internal view ; t, external view : 

 t, lower jw ; a, internal view ; i, external view : 3, teeth when the Jaws are 

 i-hul seen in profile. From 1 . Curler. 



The articulation of the condyles of the lower jaw in which this 

 formidable apparatus is set is so contrived as to cause its operation 

 in the most efficient manner. These processes are situated in the 

 pame straight horizontal line ; they are cylindrical, and firmly locked 

 in the transversely elongated glenoid cavities, the margins of which 

 are so extended both before and behind the condyle that rotatory 

 motion is impossible. The crowns of the molar or rather lacerating 

 teeth are compressed, and covered with enamel, as indeed are those 

 of all the others : the molars terminate in pointed processes, and 

 the lower teeth shut within the upper. Thus, when called into 

 action, the teeth and jaws operate like the antagonist blades of a 

 pair of scissors upon the substance submitted to their cutting edges. 

 The canine teeth, the principal prehensile weapons of the head, are 

 very long and large, especially in the larger Cat*. If we examine 

 the cranium of a lion or tiger we shall be at no loss to discover the 

 machinery by which this dental apparatus is worked. 



KkaU of Uaa seen from shore, thawing the extent of the ivgomalic archen 

 and temporal COM*. 



The Crista Occipitaliit, which is most strongly marked in tin- 

 cats, is a sharp and prominent bony ridge rising from the. upper and 

 iind portion of the skull. Us chief use is for the attachment of 

 the temporal muscle, and the size of the temporal fossa, and the 

 Htrength and extent of the zygomatic arch depend upon the magnitude 

 of that muscle. In no animals is this fossa larger than in the 

 Carnitora. It not only occupies the whole of the sides and upper 

 part of the skull, but is still further increased by the prominent 

 bony create proceeding from the frontal, parietal, and occipital bones. 

 The temporal muscles would indeed almost completely cover the 

 cranium in many of these animals, were it not for their separation 

 by the parietal ridge. 



Skull of Lion seen in profile, showing: the prominent bony crest*. 



The zygomatic suture is so oblique that the temporal bone forms 

 the whole superior margin, and the os malic the inferior edge of the 

 zygoma. 



In consequence of the construction which we have endeavoured 

 to explain, the lower jaw is capable of motion only upwards and 

 downwards, and entirely incapable of that motion in a horizontal 

 direction, which is necessary to mastication, properly so called. 

 Accordingly the Cats cut and lacerate their food coarsely, and transmit 

 it in large portions to the stomach, there to be acted on by the gastric 

 juice. 



The muscles of the neck and fore quarter of the Cats are espe- 

 cially powerful to give full effect to this part of the organisation, 

 and to enable the animal to drag or carry away its prey. 



We must next turn our attention to the other organs of 

 prehension, the claws. 



The five toes of the anterior and four toes of the posterior 

 extremities of the Cats are armed with very strong, hooked, sub- 

 compressed sharp claws. These extremities, the anterior ones espe- 

 cially, thus become powerful instruments for seizing and rending the 

 prey. The muscles that arc to wield these weapons are of great 

 strength ; those of the fore arm especially, which in the lion and 

 tiger offer the same arrangement for flexion, extension, pronation, 

 and supinatiou, as is observed in man, are highly developed, and the 

 blow alone which the animal can deal with this limb is frequently 

 fatal. It is asserted that the Bengal Tiger has been known to 

 fracture the skull of a man with one stroke of its heavy paw. The 

 claws, by a beautiful conformation, are always preserved without 

 effort from coming in contact with external bodies, so as to keep 

 them sharp and ready for action. There are some interesting 

 specimens in the Museum of the Royal College of Surgeons in 

 London, which will illustrate this provision. No. 287 of the 

 'Physiological Series' is a toe from the right fore foot of a lion, 

 with the last phalanx retracted on the ulnar (which from the prone 

 state of the foot is the outer) side of the second phalanx. This state 

 of retraction is constantly maintained, except when overcome by on 

 extending force, by means of elastic ligaments, two of which have 

 bristles placed beneath them in the preparation. The principal one 

 arises from the outer side and distal extremity of the second phalanx, 

 and is inserted into the superior angle of the last phalnux ; a second 

 arises from the outer side and proximal end of the second phalanx, 

 and passes obliquely to be inserted at the inner side of the base of 

 the last phalanx ; a third, which arises from the inner side and 

 proximal extremity of the second phalanx, is inserted at the some 

 point as the preceding. The tendon of the flexor profuudus perforans, 

 which is the antagonist of the ligaments, has been divided. No. 287 

 A is a toe from the left fore foot of a young lioness, with the last 

 phalanx drawn out, as in the action of the flexor profuudus. The 

 same ligaments are shown as in the preceding preparation, together 

 with the insertion of the flexor and extensor tendons. In order to 

 produce the full effect of drawing out the claw, a corresponding 

 action of the extensor muscle is necessary to support and fix the 

 second phalanx; by its ultimate insertion in the terminal phalanx, 

 it serves also to restrain and regulate the actions of the flexor muscle. 

 A bristle is placed beneath that part of the extensor tendon which 

 pastes under one of the elastic ligaments to be inserted into the 

 base of the loot phalanx immediately above the articulation. In 

 both preparations lateral processes of tendon may be observed going 

 to the under part of the base of the phalanx, which arc partly inserted 

 there, and partly lost in the integument : they arc given off from the 

 extensor tendon as it passes over the proximate phalanx, and are 

 | joined by lignmentous fibres from the sides of the same phalanx. 



