468 



MOVEMENTS VOICE AND SPEECH. 



of its strength and elasticity. Attached to the inner surface of the sarco- 

 lemma, are small, elongated nuclei with their long diameter in the direction 

 of the fasciculi. These .are usually not well seen in the unaltered muscle, but 

 the addition of acetic acid renders the muscular substance pale and destroys 

 the striae, when the nuclei become distinct. 



Water after a time acts upon the muscular tissue, rendering the fasciculi 

 A somewhat paler and larger. Acetic 



acid and alkaline solutions efface the 

 striae, and the fibres become semi-trans- 

 parent. In fasciculi that are slightly 

 decomposed, there is frequently a sepa- 

 ration at the extremity into smaller 

 fibres, called fibrillae. These, when 

 isolated, present the same striated ap- 

 pearance as the primitive fasciculus ; 

 viz., alternate dark and light portions. 

 They measure about -^^or f an i ncn 

 (1 /A) in diameter, and their number, 

 in the largest primitive fibres, is esti- 

 mated at about two thousand (Kolli- 

 ker). The interior of each primitive 

 fasciculus is penetrated by a very del- 



FIG. 151. Striated muscular fibres ; magnified 250 

 diameters (Sappey). 



A, transverse striae and nuclei of a primitive f ascic- i pa fa m p hra n p r>l npl v n vrnn n rl i n tt 

 ulus; B, longitudinal striae and fibrillae of a 1Caie .lOSGiy mg 



the fibrillae. This arrangement may 



primitive fasciculus in which the sarcolemma 

 has been lacerated at one point by pressure. 



be distinctly seen in a thin section of 

 a fibre treated with a solution of common salt in water, in the proportion of 

 five parts per thousand (Kolliker). 



Connective Tissue. In the muscles there is a membrane surrounding a 

 number of the primitive fasciculi. This is called the perimysium. The 

 fibrous membranes that connect together the sesecondary bundles, with their 

 contents, are enclosed in 

 a sheath enveloping the 

 whole muscle, sometimes 

 called the external peri- 

 mysium. The peculiari- 

 ty of these membranes as 

 distinguished from the 

 sarcolemma is that they 

 have a fibrous structure 

 and are connected togeth- 

 er throughout the muscle, 

 while the tubes forming 

 the sarcolemma are struct- 

 ureless and each one is 

 distinct. 



The name now most generally adopted for the ordinary fibrous tissue is 



PIG. 152. Fibres of tendon of the human subject (Rollett). 



