MYOLOGY. 



By G. D. THANE. 



THE MUSCLES IN GENERAL. 



UNDER this section will be brought the description of most of the Voluntary 

 or Skeletal Muscles of the body, the exceptions being certain intrinsic muscles of 

 the auditory apparatus, of the tongue, and of the larynx, which will be considered 

 in connection with the organs of which they form part. Along with the muscles 

 the Fasciae and Aponeuroses by which they are invested will be described. 



The voluntary muscles are for the most part placed in close relation with the 

 endoskeleton, being attached to the bones or other hard parts, and moving these in 

 different directions by their contractions. There are, however, some muscles which 

 may be looked upon as belonging to the cutaneous system, or exoskeleton, and there 

 are a few others which are connected with the viscera. The muscles are all 

 symmetrical, and, with the exception of the sphincters and one or two others, are 

 in pairs. 



The total number of voluntary muscles may be stated at 311, there being some 

 variation above or below that number according as certain muscular parts are 

 regarded as separate and independent muscles or only as portions of others. They 

 naturally fall into the following great divisions, viz. : 



A. In the axial part of the body. 



1. The muscles of the head and front of the neck = 82. 



'2. The muscles of the vertebral column and back of the neck = 60. 



3. The muscles of the thorax = 42. 



4. The muscles of the abdomen =14. 



B. In the limbs. 



.">. The muscles of the upper limb = 59. 

 (>. The muscles of the lower limb = 54. 



In this enumeration the muscles of one side only are reckoned, the intrinsic muscles of the 

 ear. tongue and larynx are included, and various short muscles serially repeated, such as the 

 intercostals, levatores costarum, interspinales, &c., are counted separately, while the erector 

 spinae and quadriceps extensor cruris are regarded as single muscles. 



In the detailed description of the muscles the foregoing divisions will be 

 generally followed, but it may be expedient occasionally to deviate from the strictly 

 systematic arrangement, in so far as may conduce to facility in study and con- 

 venience in dissection. 



Each muscle constitutes a separate organ, composed chiefly of a mass of the con- 

 tractile fibrous tissue which is called muscular, and of other tissues and parts which 

 may be looked upon as accessory. Thus the muscular fibres are connected together 

 in bundles or fasciculi (see General Anatomy), and these fasciculi are again embedded 

 in and united together by a quantity of connective tissue, forming the perimysiwu, 



