STRUCTURE OF MUSCULAR TISSUE. 



309 



sequence of the prolongation of certain fibrillae beyond others. Prof. Kb'lliker 

 describes the terminal fibrillae as occasionally losing their transverse striae, and 

 as passing with apparent continuity into the fibrils of the tendon, the myolemma 

 not being continued over the extremity of the fibres; but it has always appeared 

 to the Author, that the connection between the muscle and the tendon is esta- 

 blished rather through the medium of the myoleinma than through that of the 

 fibrillae. Where the muscular fibre terminates in a broad flat disk (Fig. 98), 



Attachment, of Tendon to Muscular Fibre, in Skate. 



the tendinous fibres appear at first to stop short upon its surface ; but a more 

 careful examination will generally enable them to be traced over the myolemma 

 of the cylindrical portion of the fibre; and the Author has occasionally seen in- 

 dications of a double spiral arrangement of these fibres around the sheath of the 

 muscular fibre, which has also been described by Dr. Leidy. When the fibres 

 of a muscle are inserted more or less obliquely into the side of a tendon whose 

 fibres take a different direction, the muscular fibres are attached by rounded or 

 blunt conical ends to the side of the tendinous fasciculi, which are excavated 

 into little shallow pits or dimples to receive them ; and the continuity of the 

 myolemma over their extremities can then then be 

 distinctly made out. Fi S- " 



305. The plain, smooth, or non-striated form of 

 Muscular tissue, ordinarily presents itself in the con- 

 dition of flattened bands, whose diameter is usually 

 between l-2000th and l-3000th of an inch; their 

 substance is translucent, but sometimes finely granu- 

 lar; and they are usually marked at intervals by 

 peculiar elongated nuclei, which, when not originally 

 visible, may be rendered so by acetic acid (Fig. 99). 

 These bands are generally collected into fasciculi, in 

 which they lie parallel with one another; but the 

 fasciculi themselves often cross each other and inter- 

 lace. They have not, as a general rule, fixed points 

 of attachment, like those of the muscles composed 

 of striated fibres ; but form continuous investments 

 around cavities lined by mucous or other membranes, 

 as the alimentary canal, the uterus, the bladder, the 

 vascular trunks, &c. ; or are dispersed through the 

 substance of other fibrous tissues, especially the skin, 

 to which they impart a contractile property. This 

 tissue, however, has lately been resolved by Prof. 

 Kb'lliker 1 into a yet more elementary form ; for he 



Non-striated Muscular Fibre; at 

 &, in its natural state ; at a, showing 

 the nuclei after the action of acetic 

 acid. 



Kolliker and Siebold's Zeitschrift," 1849. 



