NECROSIS OF TISSUES. 9 



By tills coagulation tlie protoplasm is rendered incapable of 

 movement; it stiffens in an attitude which corresponds to the 

 "quiescent state" of the cell; the granules, too, which may 

 previously have exhibited some sort of molecular movement, 

 become stationary ; the whole structure puts on a dull and dusty 

 look,* finally breaking up into granules of large relative size, 

 which then shrink and disappear. The nucleus, which was at 

 first rendered more distinct, also falls a prey to this disintegra- 

 tion. 



§ 13. The course of events is naturally modified in accordance 

 with the previous physiological development of the cells. Our de- 

 scription is unconditionally applicable to the cells of the connective 

 tissue, of the rete Malpighii, and of those deeper layers of other 

 epithelial membranes which correspond in position to the rete ; also 

 to the secreting cells of glands, and to lymph corpuscles. But 

 the limitary membrane with which the older epithelial cells are 

 furnished offers a strenuous resistance to the solvent process. 

 Hence these cells retain their form long after their nucleus and 

 their protoplasm (here = cell-contents) have been broken up into 

 granules ; so that epithelium cells, destitute of nuclei, are con- 

 stantly to be met with in mortified parts. In this respect the 

 cells of the epidermis take a foremost place; the duration of 

 their resistance to the necrotic process being proportionate to the 

 deofree of their cornification.t 



§ 14. The FIBRES OF UNSTRIPED MUSCLE, tliough not endowed 

 with a limitary membrane, retain their peculiar aspect for a com- 

 paratively long time ; their nuclei are often only to be traced 

 by an elongated mass of dots, while their marginal outlines are 

 still as distinct as ever. The phenomena of rigor mortis have 

 been but little studied in the contractile substance of unstriped 



* KiUuie failed to observe this change in the cells of the areolar con- 

 nective tissue, but he saw it in the corneal corpuscles of the frog. ( W. 

 Killine, " Researches on Protoplasm and Contractility." Leipzig, Engel- 

 mann, pp. 121-130.) 



t We must bear in mind, however, that cornification is itself a 

 gradual transition from life to death. I may add, by the way, that 

 during cornification a shrinking and final disappearance of the nucleus 

 may also be observed. 



