80 TRANSVERSELY STRIPED MUSCULAR FIBRES. 



Very dilute sulphuric acid acts in the same manner as acetic 

 acid, or extremely dilute hydrochloric acid. 



A concentrated solution of chromic acid causes the muscular 

 fibres to be resolved, after prolonged action, into parallelepipeds of 

 an intense yellow colour, some of which exhibit a sharply defined 

 longitudinal striation without any perceptible transverse striae, 

 whilst others are characterised by the most beautiful and delicate 

 transverse striation. Both in the longitudinally and transversely 

 striated portions we frequently find four, five, or even more trans- 

 verse rents and clefts, but never any cleavage in the longitudinal 

 direction. Many of the fibres are broken up into irregular flakes ; 

 but the muscular fibres do not in any case appear to resolve them- 

 selves into definitely formed morphological elements. The sarco- 

 lemma is gelatinous and finely granulated. 



When a muscular fibre has been exposed to the prolonged action 

 of a saturated solution of bichromate of potash, the transverse striae 

 stand sharply out, whilst the fibre corresponding to them is torn 

 at different spots, or exfoliated in the individual transverse striae. 



When small carefully prepared portions of muscle are digested 

 for a long time at a temperature of from 30 to 40, in a solution of 

 six parts of nitrate of potash in 100 parts of water, no solution of 

 one or other of the elementary parts of the muscular tissue can be 

 observed. The transverse striation is generally visible in the 

 primitive bundles, while the longitudinal striae are rendered far 

 more conspicuous. I know of no menstruum which so clearly 

 exhibits the longitudinal cleavage of the muscular bundle pro- 

 jecting from the sarcolemma. This projecting portion splits in 

 the form of a tuft into diverging, primitive longitudinal fibres, 

 which individually exhibit distinct transverse striae. These, how- 

 ever, do not exhibit the form of varicose dilatations of the fibrils, 

 but present the appearance of clear and light spots, which suc- 

 ceed one another in a very regular manner, and have the same 

 transverse diameter. The fibres appear as if composed of linearly 

 arranged parallelepipeds of translucent but not transparent sub- 

 stance. (F. P. 15, F. 4.) 



Pieces of muscle, when exposed for a prolonged period to the 

 action of sub-nitrate of mercury (with the nitrite), are converted 

 into a violet coloured, hard brittle mass, which admits of being 

 reduced to a nearly purple-coloured powder. When examined 

 under the microscope, the muscular bundles appear in the form of 

 pale bluish red parallelepipeds, which exhibit the most delicate 

 and sharply defined transverse striation. In thin sections, cut 



