G6 CONTRACTILE FIBRE-CELLS. 



tions. By the prolonged action of the acid the suhstance of the 

 cell is dissolved^ leaving, in addition to amorphous granules, 

 nothing but nuclei, which now, for the most part, assume some- 

 what the form of cucumber-seeds. The fibres of connective 

 tissue, which are occasionally present, appear as very transparent, 

 broadened, perfectly homogeneous bands. I was much surprised 

 to find, on examining organic muscles which had been frequently 

 washed in water, and macerated for a long time, that no nuclei 

 could be rendered visible either by the dilute acetic or hydro- 

 chloric acid. (F. P. 14, F. 6.)* Henlef was led to infer, from the 

 result of his experiments, that the superficial layer always soonest 

 undergoes decomposition, and hence its nuclei are first destroyed. 



The fibres shrivel up very readily in concentrated hydrochloric 

 acid, but the nuclei are not rendered more transparent. After a 

 prolonged exposure to the action of the acid, entire, finely striated 

 bundles are brought into view. Water causes the fibres to swell, and 

 form thick, sharply outlined strings, in which state they resemble 

 the representations (or rather the diagrams) formerly made by 

 histologists of normal organic muscular fibres. 



Concentrated sulphuric acid renders the bundles of fibres more 

 transparent and gelatinous ; after the repeated addition of water the 

 bundles contract, and again appear distinctly fibrous (Bonders). No 

 nuclei can be distinctly recognised, but I have frequently observed 

 in preparations which had been treated with concentrated sul- 

 phuric acid, and after the repeated addition of water, the existence 

 of coarse granules of an oval or irregularly rounded shape and 

 isolated fat-globules, whilst the other histological elements had 

 wholly disappeared. 



The fibre-cells become somewhat contracted in concentrated 

 cold nitric acid, and exhibit a curled appearance. The smaller 

 ^bundles are divided into isolated fibrils of a pale yellow colour ; 

 no nuclei can be detected with certainty ; the fibres of connective 

 tissue remain smooth and narrow, and are not coloured yellow. 

 The yellow colour appears in a remarkably beautiful manner in 

 the fibre-cells on applying caustic ammonia to the object after it 

 has been treated with nitric acid. The fibre- cells are perfectly 

 dissolved in boiling concentrated nitric acid, whilst nothing appears 

 in the fluid beyond a few scattered fat-globules. 



A concentrated solution of chromic acid renders the bundles of 

 smooth muscle so perfectly soft that they break up on the 



* The abbreviation for Funke's Atlas, Plate 14, Fig. 6. 

 t Jahresber. der ges. Med. 1851, S. 44. 



