MUSCULAR TISSUE. 



ISl 



4. The muscular tissue of the crayfish alwaj-s has the 

 form of bands or fibres, of very various thickness, marked, 

 when viewed by transmitted light, by alternate darker and 



Fig 



52. — Atitdciis fiiridtUls. — A, a siugle muscular fibre, transverse 

 diameter jLtli of an inch ; B, a portion of the same more highly 

 magnified ; C, a smaller portion treated with alcohol and acetic 

 acid still more highly magnified ; D and E, the splitting up of a 

 part of a fibre, treated with picro-carmine, into fibrillar ; F, the 

 connection of a nervous with a muscular fibre which lias been 

 treated with alcohol and acetic acid, n, darker, and /', clearer portions 

 of the fibrillas ; n, nuclei ; ni\ nerve fibre ; .«, sarcolemma ; t, tendon ; 

 1 — "), successive dark granular striaj answering to the granular 

 portions, a, of each fibrilla. 



