MUSCLES 275 



to a bone; there is always a tendinous tissue between them, 

 although it may not be noticeable. On the other hand 

 the tendon may be very long; for example, some of the mus- 

 cles which move the fingers are near the elbow; Fig. 138. 

 The advantage of this is obvious; for if the muscles were lo- 

 cated in the parts used, these would be unwieldy and large. 

 Imagine the size and awkwardness of the fingers for example, 

 if all the muscles concerned in their work were located im- 

 mediately in them. The muscles which operate a bird's leg 

 and toes are placed high up on the leg among the feathers. 

 The leg of a wading bird, like the flamingo, is a striking ex- 

 ample of this contrivance for obviating cumbersome mechan- 

 ism and allowing freedom of movement. The tendons are 

 popularly called cords. The wrist is little more than a bundle 

 of such cords around the bones. 



As Figure 137 shows, the upper part of the biceps muscle 

 is attached at the shoulder by two tendons (whence the 

 name biceps), while the lower end is fastened by a tendon to 

 the radius bone below the elbow joint but not far from it. 

 A slight shortening of the biceps will, therefore, lift the arm 

 through considerable distance. 



Microscopic Structure of Striped Muscle. If a muscle be 

 cut across, it will be found to consist of small parts, called 

 fasciculi, closely bound together, and giving a " grain " to 

 the muscle like that in a piece of raw steak. If one of these 

 fasciculi be pulled to pieces and examined with a microscope, 

 it will be found to consist of a large number of minute threads, 

 or fibres; Fig. 139. 



These muscle fibres, which are too small to be seen with 

 the naked eye, always run lengthwise but do not usually 

 extend the whole length of a muscle. These fibres are cylin- 

 drical bodies, traversed by fine cross lines, or striae, which 

 gives rise to the name " striped muscle." Each fibre consists 

 of an outer tube, the sarcolemma, and a jelly-like substance 

 within. It is this soft material in the tube which is the 



