408 



THE TISSUES. 



SECTION II. 

 STRUCTURE OP THE MUSCLES. 



The muscles consist of striated muscular tissue, areolar tissue, 

 vessels, and nerves; and all the longer fusiform muscles (as of the 

 extremities) contain a considerable amount of 

 the white fibrous tissue also. 



The last-mentioned muscles may each be 

 divided into -first, the aponeurosis of origin ; 

 secondly, the tendon by which they are inserted 



Fig. 261. 



Fig. 260. 



The aponeurosis, belly, and 

 tendon of the fusiform mus- 

 cles (flexors) on the anterior 

 aspect of the forearm. 5. 

 The flexor carpi radialis ; 

 its aponeurosis of origin is 

 seen at its upper extremi- 

 ty, next its belly above the 

 figure 5 ; and the tendon 

 below the latter. 



Transverse section of the tendon of a calf. (Magnified 20 diame- 

 ters.) a. Primary fasciculus. 6. Secondary fasciculus, c. Nuclear 

 fibres not quite in transverse section, but appearing as little streaks 

 in the former, d. Interstitial connective tissue. (KiJlliker.) 



into the bone or other organ to be moved by 

 them; thirdly, the belly, or intermediate por- 

 tion. (Fig. 260.) Each of these will be sepa- 

 rately described. 



1. The aponeuroses are composed of white fibrous tissue, and are 

 generally flattened into the form of a membrane. Their structure 

 has already been specified (p. 278, 2). 



2. The tendons are also cords of white fibrous tissue, like the 



