MUSCLES AND PHENOMENA OF CONTRACTION. 115 



such a small bundle be teased under the microscope into its 



Fig. 58. SEVERAL VOLUNTARY MUSCLE FIBRES. (After Sharpey.) 

 a, end view of fasciculus ; 6, 6, individual fibres ; c, a fibre splitting: into longitudinal 

 fibrils. 



ultimate fibres, the following points may be noticed con- 

 cerning their finer structure: 



Striation. The fibres appear cross-striped. This is not 

 due, however, to markings running on the outside of a 



Fig. 59. PORTION OF A HUMAN MUSCULAR 



FIBRE SHOWING THE ALTERNATE LIGHT 

 AND DARK BANDS, AND IN THE LIGHT 

 r.A.XI) THE MK.M15RANE OF KRAUSE. 



(After Sharpey.) 



Fig. 60. Two VOLUNTARY FIBRES. (After 



Gegenbaur.) 



n, nuclei under sarcolemma ; s, sar. 

 colemma visible where the fibre is torn. 



muscle, but it is due to the fact that a muscle fibre is com- 



