STRUCTURE OF MUSCLE. 



15 



Origin 



Bundle of Muscle. Fibers 



I 



uscle Sheath 



CROSS SECTION 



Tendon 



Insertion 



LONGITUDINAL SECTION 



work of white substance; this is the Connective Tissue. In 



the meshes is the red muscular tissue. The partitions which 



run all through the muscle, 



and the cross-sections of 



which we see in a piece of 



chipped beef, are continuous 



with the Muscle Sheath, and 



both are continuous with the 



tendons at the ends of the 



muscle. In fresh muscle 



the sheath and the partitions 



are nearly transparent, and 



are not easily seen. Whenthe 



meat is cooked or salted the 



connective tissue becomes 



opaque and is white. 



In frog's or rabbit's mus- 

 cle observe the thin, trans- 

 parent membrane covering the muscle, the muscle sheath. 

 With forceps tear away part of the 

 muscle sheath. Tear the muscle to 

 pieces, and note its fibrous structure. 

 Put a shred of muscle in a drop of 

 normal saline solution on a slide, and 

 examine with low power of the micro- 

 scope ; again examine with a higher 

 power. The cross-markings, or stri- 

 ations, will be seen. 



Such muscle is called Striated or 

 Striped Muscle. All of the muscles 

 used in ordinary motions are of this 

 kind. 

 In well-cooked corned-beef the connective tissue is thor- 



Fig. 4. The Structure of Muscle. 



Fig. 5. Two Muscular Fibers, 

 showing the Terminations of 

 the Nerves. 



