164 THE CAT. [chap. v. 



raclialis -witli the tibialis posticus ; the flexor digitorum profundus 

 with the flexor longus digitorum ; the flexor digitorum sublimis 

 with the flexor brevis digitorum ; the extensor communis with the 

 extensor longus digitorum ; the palmaris longus with the plantaris ; 

 the pronator teres with the popliteus ; while the lumbricalcs and 

 interossei generally correspond in spite of the slight differences 

 already noted. 



§ 13. Considered independently of the bony skeleton, the 

 muscular system of the cat may, as its simplest expression, be con- 

 ceived as a fleshy envelope of the body which takes the form, 

 ventrally, of three superimposed layers (the flbres being directed 

 differently in each layer), and dorsally, of a number of very various 

 longitudinal bundles, ending in tendons directed more or less 

 ' obliquely forwards. In the tail the envelope consists of longitudinal 

 bundles, which, below as well as above, end in tendons directed 

 more or less obliquely backwards. In the head, the muscular 

 envelope becomes complicated for the hyoid, jaws, and organs of 

 sense. The muscles of the limbs may bo conceived as slicaths of 

 fibres forming n. median and two lateral groups of muscles, botli on 

 the extensor and flexor surfaces of each limb, with special modifica- 

 tions and subdivisions where each limb becomes subdivided iuto its 

 terminal digits. 



