THEIR MICRO-CHEMICAL RELATIONS. 83 



can seldom be clearly distinguished. A saturated solution of car- 

 donate of potash acts upon the macerated muscles very much in 

 the same manner as chloride of calcium ; the individual bundles 

 have a very sharply defined outline, and are enlarged transversely ; 

 the longitudinal striation almost wholly disappears, and leaves the 

 transverse striation so sharply defined as to make the dark striae 

 appear much thicker than the lighter ones. Concentrated nitric 

 acid certainly causes the transverse striae in the macerated primi- 

 tive bundles to reappear ; the dimensions of the latter are consi- 

 derably diminished transversely. 



Dilute hydrochloric acid, such as that employed by Liebig,* 

 for the extraction of muscle-fibrin (1 p.m. H Cl), causes the sar- 

 colemma to come prominently into view. Pieces of muscle which 

 have been thus treated show an amount of connective tissue, and 

 more especially of nuclear fibres, far exceeding what one would 

 expect to meet with, judging from the ordinary modes of examining 

 muscular tissue. As has already been observed, the individual 

 portions of sarcolemma bear a strong resemblance to the cylinders 

 in the urine in Bright's disease ; they have a much smaller diameter 

 than the primitive bundles which they surround. The smaller 

 portions of sarcolemma are entirely empty, and are simply inter- 

 spersed here and there with granules of various sizes. In the 

 longer pieces of sarcolemma the nuclei appear irregularly disposed, 

 near and amongst one another, and, in addition to the nuclei 

 and granules, there appear at intervals bodies similar to masses 

 of fat, sometimes resembling the pulp which protrudes from the 

 nervous fibres, or at other times appearing as very small granular 

 cells. The true membrane of the sarcolemma is extremely hyaline, 

 and can generally be only clearly made out by the aid of very 

 good illumination and simultaneous shading with the diaphragm. 

 When these preparations are acted upon by a saturated solution of 

 carbonate of soda, the nuclei and a portion of the granules dis- 

 appear, and the sarcolemma becomes almost more hyaline. Con- 

 centrated nitric acid also causes the nuclei to disappear, but colours 

 the sarcolemma yellow, whilst the connective tissue remains 

 uncoloured. This difference of colour is rendered very conspi- 

 cuous on saturating the acid with potash. Chromic acid also 

 imparts to the sarcolemma a very beautiful yellow colour, whilst, at 

 the same time, it contracts it to so great a degree that the diameter 

 is scarcely one-third or one-fourth of that of the original primitive 

 bundle ; the nuclei disappear entirely. On adding a very dilute 



* Ann. d. Ch. u. Pharm. Bd. 73, S. 125-129. 



G2 



