Connective Tissue, Nerve, and Muscle. 525 



By combining several methods of investigation, I believe I have suc- 

 ceeded in clearing up some points in the anatomy of muscular fibre, 

 by which it will be seen that, as regards the lymphatic system, muscle 

 occupies a position almost identical with tendon and connective tissue 

 generally. 



If fresh muscle is deeply stained with haematoxylin and then treated 

 by acetic acid and gently teased, the perimysium of the bundles and its very 

 fine continuation around each fibre are seen to be studded with large round 

 nuclei, which are far more numerous than those of the branched cells, 

 which are also seen. The round nuclei belong to the flat cells of the 

 perimysium. 



I have been able to demonstrate the character of the cells by teasing 

 the living muscle of the frog in aqueous humour, and thence transferring 

 the separated fibres to the nitrate-of-silver solution. The usual sinuous 

 lines are then seen both on the general and special perimysium. This is 

 represented in figures 5 and 6, Plate IX. 



When muscle is treated by the saturated solution of potash, as above 

 described, the fibres are found unaltered, the striated appearance being 

 well marked. There is no vestige left of the perimysium. On the naked 

 surface of the sarcolemma, a number of round distinct nuclei are seen ; and 

 when they happen to be on the edge of the fractured fibre, it is seen that 

 they are situated on its outer surface. 



If the saturated potash solution in which the muscle is placed is kept 

 for about an hour at a temperature of 110 Fahrenheit, and then allowed 

 to cool gradually, we find a further effect has been produced. 



On breaking down a piece of the muscle into its individual fibres, we 

 find that although some of these are unaltered, others have lost all their 

 nuclei, and present the appearance of a coarse granular cylinder. But 

 there is sometimes a transition stage seen of peculiar interest. On the 

 surface of the fibre the outlines of a series of quadrangular cells make 

 themselves visible, each cell having a distinct nucleus ; and it is easy to 

 satisfy one's self that the nuclei of the cells are identical with the nuclei 

 seen previously distributed over the surface of the sarcolemma. These 

 cells are sometimes also seen free in the solution, in which case they are 

 generally more or less broken up, but sometimes they ar"e seen isolated 

 in perfect condition. Figure 21, Plate XI., shows the cells becoming de- 

 marcated on the fibre, and figure 22, Plate XI., their appearance when 

 isolated entire. The sarcolemma is sometimes seen freed both from the 

 cells and their contents ; and in this case the striped cylinder which may be 

 seen near it is beset with small perforations. 



The sarcolemma of muscle is thus covered with flat cells, regular in appear- 

 ance and outline, which resist the action of a saturated solution of potash. 



But the action of the potash teaches us something more. A fibre is 

 sometimes found apparently unaltered, smooth in its contour, and still 

 showing something of the striated appearance, but showing no nuclei. 



