154 



THE CAT. 



[CHAP. v. 



and an extensor inserted into every segment from the metacarpal to 

 the last phalanx is only attained in the index and the digitus 

 minimus. 



Thus in these digits the metacarpal bones are flexed by the flexor 

 carpi radialis and flexor carpi ulnaris respectively, while no other 

 metacarpal has a separate flexor. They are extended by the 



extcnsores carpi radialis longior 

 and ulnaris respectively. The 

 first phalanx of each is flexed 

 by the interossei, and extended 

 by the extensores indicis and 

 minimi digiti respectively. The 

 second phalanx of each is flexed 

 by the flexor perforatus and 

 extended by the extensor com- 

 munis digitorum. The ultimate 

 phalanx in each is flexed by 

 the flexor peribrans and ex- 

 tended by subdivisions of the 

 interossei (aided by the lum- 

 bricales), which join the ex- 

 tensor sheath and are finally 

 inserted into the distal phalanx. 



- Ta 



Fig. 82. SUPERFICIAL MUSCLES OF THIGH. 



Ji. Biceps femoris. 



G. Gastrocnemiiis. 



G mx l and G mti*. Glutens maximus. 



M. Semi-membranosus. 



S. Sartorius. 



T. Semi-tendinosus. 



T a. Tibialis anticus. 



T vf. Tensor vaginae femoris. 



MUSCLES OF THE HIND LIMB. 



10. The muscles of the 

 Idp and thigh, though mainly 

 taking origin from the pelvis 

 and leg bones, yet partly arise 

 from the loins. 



The ghitem maximus con- 

 sists of a great sheet of muscle 



and tendinous aponeurosis, and is more or less divisible into two parts : 

 one arises, by fascia, from the membrane covering the sacral region 

 dorsally, and, by some muscular fibres, from the sacrum itself ; the 

 other part arises, by muscular fibres, from the first two caudal vertebra?. 

 The first part is inserted into the great trochanter, at the base of its 

 hinder outer part. The second part of the gluteus maximus is in- 

 serted into the femur below of the great trochanter, by means of a 

 sheet of fascia (the fascia lata), which invests the thigh, dipping in 

 between the adductor and the vastus externus, and descending right 

 down to the external condyle of the femur. 



The tensor ragiuce femoris is a large thick muscle which arises from 

 the anterior end and anterior half of the ventral margin of the ilium, 

 and from the dense fascia intervening between it and the first part 

 of the gluteus maximus. It is inserted into the fascia lata, which dips 

 in (as before said) between the adductor and the vastus externus. 



