146 MUSCULAR SYSTEM. 



cover of the flexor tendons. They are longer but thinner than 

 the former, and may be classed among the half-pen niform muscles. 

 They adhere for some way down the leg to the small metacarpal 

 bones, become tendinous about the middle of the cannon, turn 

 round the tuberculous terminations of the small metacarpals, and 

 vanish in the adipose substance in front of the limb connected 

 with the extensor tendons. 



Action. — The use of these small muscles seems not to be 

 known; at least, it is by no means well defined. 



MUSCLES OF THE HIND EXTREMITIES. 



The muscles of the hind extremity are invested and closely 

 compacted together by a subcutaneous covering, in part ten- 

 dinous and in part cellular in texture (according to the dif- 

 ferent structures in the vicinity from which we find it to be 

 derived), to which we may give the name (analogically) of 

 faschia lata. In front of the haunch it is derived from the 

 panniculus and crural arch, and is both fibrous and cellular in 

 composition ; on the outer side of the haunch it is continued 

 from the tensor vaginae, a muscle that may be said to belong 

 or have an exclusive relation to it; on the inner side, it is con- 

 tinuous with the faschia superficialis abdominis, faschia scroti 

 et pubis, and is entirely cellular in structure; and posteriorly, 

 it is connected with the faschia lumborum. The principal 

 fixed points of attachment of this faschia are, the anterior spine 

 of the ileum, the pubes, the coccyx, the trochanter minor ex- 

 ternus, and the patella. Inferiorly, it spreads upon the muscles 

 of the leg, giving them a compact investment, which portion of 

 it maybe denominated the crural or tibial faschia : it derives 

 various fibrous additions from the tendons of the gracilis, sar- 

 torius, seniitendinosus, triceps, Sec, and finally vanishes in ex- 

 pansion over the hock. The external surface of the faschia is 

 adherent to the skin, through the intervention of a delicate 

 cellular tissue; there being included between them, besides 

 more or less adipose matter, the subcutaneous bloodvessels, 

 nerves, and lymphatics. Its internal surface is applied to the 

 muscles themselves, and between several of them it sends down 

 processes which take root in the bone. From the faschia itself 

 in some places the muscular fibres appear to aiise. 



The use of the faschia lata appears to be, to give both power 

 and effect to the muscles during the time of their action, by 

 retaining them in their respective places and relative positions, 

 and keeping them closely and compactly braced together. 



