OP THE MUSCULAR SYSTEM IN*GENERAL. 311 



SECTION I. 



OP THE MUSCULAR SYSTEM IN GENERAL. 



653. The muscular system forms of itself a great portion 

 of the weight and volume of the body. 



654. However diversified may be their form and situa- 

 tion, the greater part of the muscles are divided into bundles, 

 and are all formed of primitive or simple fibres, collected into 

 fasciculi. 



The authors who have treated on this point of minute ana- 

 tomy, have in general presented it in a manner but little in- 

 telligible: some simply observe, that the flesh is composed 

 of fibres; others, of fleshy stria?; others again, of fibres and 

 fibrils; and lastly, others state that it is composed of fibres, 

 themselves composed of villi. Muys has made a ternary divi- 

 sion. He divides the muscular flesh into fibres, fibrils and 

 threads. He subdivides the fibres into three orders: large, 

 mean and small; the large being composed of the mean, and 

 the latter of the small fibres; the same with respect to the 

 fibrils, the smallest of which compose the mean, and these 

 compose the largest, the latter composing the smallest of the 

 fibres; the same again as to the threads, of which the most 

 minute of the fibrils are composed; according to this doc- 

 trine, the muscles would be the result of nine successive de- 

 grees of composition. 



Others, rejecting this analysis as altogether imaginary, ad- 

 mit an infinite divisibility. But it is well established, on the 

 contrary, that, with respect to the muscles, as with all organic 

 substance, we arrive by microscopic inspection, at a degree of 

 division finite and well determined. 



655. The muscular bundles, lacerti, are not equally dis- 

 tinct, numerous and voluminous in all the muscles; the bundles 

 composing some of them, are so distinct and large that they 

 may be considered as so many particular muscles: such are 

 the portions of the biceps, triceps, the bundles of the deltoid, 

 of the masseter, of the glutaeus magnus, &c.; such are also 



