VERTEBRATA : MAMMALIA. 



749 



molars (fig. 423) are fewer in number than in any other of the 

 Carnivora (hence the shortness of the jaws), and they are all 

 trenchant, except the last molar in the upper jaw, which is 

 very small and is tuberculate. The upper carnassial has three 

 lobes, and a blunt heel or internal process. The lower car- 

 nassial has two cutting lobes, and no internal process. The 

 dental formula is 



'& ' 



f" tl ; - r i - 3- 



The legs are nearly of equal size, and the hind-feet have 

 only four toes each, whilst the fore-feet have five. All the 

 toes are furnished with strong, curved, retractile claws, which, 

 when not in use, are withdrawn within sheaths by the action of 

 elastic ligaments, so as not to be unnecessarily blunted. The 

 ungual phalanges (fig. 436) are strongly bent near their middle, 

 and the resistance of the ligaments which retract the claws is 

 overcome (when the claws are to be protruded) by the con- 

 traction of the flexor profundus perforans. The tongue is 



Fig. 436. Bones and ligaments of the toe of a Cat, showing the claw retracted (A) 

 and protruded (B). 



roughened and rendered prickly by the presence of horny 

 papillae, thus rendering it a most efficient rasp in licking the 

 flesh from the bones of the prey. All the members of this 

 group are exceedingly light upon their feet, and are exces- 

 sively muscular, and they have all the habit of seizing their 

 prey by suddenly springing upon it. 



It is questionable if any good genera have hitherto been 

 established in this family, as far as recent forms are concerned, 



