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PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



across the fibre at regular intervals (membrane of Krause). Within this 

 is inclosed the sarcous substance, or the contractile tissue of the muscu- 

 lar fibre, which is a broad, highly refractive, doubly refractive disk, and 

 the nuclei or muscle-corpuscles. The muscle-corpuscles are thus within 

 the sarcolemma, and it is at the expense of their protoplasm that 



Fig. 271.— Muscular Tissue, after Gkrlach. (Ellenberger.) 



,1, scheme of the different parts of striped muscular fibre : S. sarcolemma ; K, nucleus: 2, striation; 

 F, fibrillar ; N, nerve ; E, nucleated nerve-plate ; 2, part of a cross-section ; 3, isolated fibrillje ; 4, highly 

 magnified fibril of insect muscle; A. Krause-Amici's line ; B, anisotropic substance ; C, central disk ; D, 

 isotropic substance ; o, separation of disks ; (>. cell of heart-muscle of frog ; 7, embryonal development of 

 muscular fibre : 8, cells of heart-muscle ; 9. cross-section of heart-muscle ; 10, unstriped muscle-cells ; 11, 

 cross-section of unstriped muscle-cells; 12, muscular fibre with tendon; IS, interfibrillar muscular 

 nerves. 



muscular tissue is formed. Between the contractile disks and Krause's 

 membrane is a transparent, isotropic, semifluid layer (the lateral disk 

 of Engelmann), which is composed of prismatic, rod-shaped elements, 

 the sarcous elements of Bowman. 



