ORIGIN OF THE DOMESTIC CAT 157 



Herbivora, but only an up and down chopping or 

 cutting motion, while the teeth, especially the 

 canines, are enormously developed. Again, the 

 almost globular form of the bulla tympani, and the 

 division of the cavity into two portions by a bony 

 partition, are also distinctive characters of the 

 Felidse. 



2. The structure of the foot is peculiar, inasmuch 



MECHANISM OF THE CAT's CLAW. 



(Twice Natural Size. From a Sketch by T. J. Parker,) 



A., with the claw retracted; B., with the claw exserted ; w:/c., the metacarpal; 

 ph. 1, the fir^t ; ph. 2, the second ; ph. 3, the third phalanx ; A,, the bony "hood " ; 

 c, the claw ; /., the elastic ligament ; t., the flexor tendon ; a., a. ligamentous loop, 

 through which the tendon passes. 



as the cats (with the exception of the Cheeta) are 

 the only animals which possess the power of retract- 

 ing the claws. This is effected by means of a 

 peculiar modification and arrangement of the second 

 and third joints of the toes, the iMrd being pulled 

 back by an elastic ligament upon the second, when 

 not forcibly extended by means of the strong flexor 

 muscles which run along the under surface of the 

 foot. 



