NECROSIS OF TISSUES. 13 



the cells wliich normally contain it; tlie liberated oil globules 

 coalesce to form larger drops, giving the sanies gangrcenosa (§ 22) 

 the peculiar aspect of an emulsion, and permeating all the mor- 

 tified tissues so thoroughly, tliat it becomes very difficult to get 

 a specimen all whose chinks and crevices are not occupied by a 

 countless multitude of oil globules. 



If we bring the adipose tissue itself under the microscope, 

 we hardly see a single fat-cell which still retains its normal 

 amount of oil ; it must, however, be added that it is equally hard 

 to find one which has parted with the whole of its contents. The 

 contained oil globules are mostly reduced to half their usual size ; 

 they are often broken up into smaller globules. This residual 

 oil is peculiarly prone to imbibe hsematin, so that not only the 

 cell membranes and the lax connective tissue between the clusters 

 of fat-cells, but the entire pamiiculus adijwsus becomes stained 

 of a red, or reddish yellow colour. Crystals may form in the 

 interior of the cells ; but they are far more often to be found in 

 the oil which has been set free ; hence they are a constant ingre- 

 dient of the gangrenous sanies (see § 23). 



§ 18. The first change exhibited by the fibres of the loose 

 COXXECTIVE TISSUE is a simple swelling. Tliis does not add to their 

 transpai'ency, like the swelling caused by acetic acid ; on the 

 contrary they become more opaque, and refi'act light more 

 highly. Tliis change is usually associated with the imbibition of 

 blood pigment, alluded to above, the depth of colour produced 

 varying inversely as the amount of water present. For it need 

 hardly be explained that the degree of swelling is exactly pro- 

 portionate to the quantity of water in the tissue. The evaporation 

 and re-absorption of the fluid from the parenchyma are at once 

 announced by a corresponding desiccation of the fibrillar of the 

 connective tissue. The coal-black substance into which the cutis 

 is converted by dry gangrene exhibits, in fine sections, a ruby- 

 red colour by transmitted light. 



Should the fibres continue to swell, they become granular, 

 their outlines wax indistinct, and they finally melt away into a 

 turbid slime. 



§ 19. The formed constituents of the connective tissue offer a 

 far more vigorous resistance than its basis substance. I refer less 

 to the glassy, homogeneous membranes (capillaries, tunicas pro- 

 pria?, basement membranes), concerning whose fate during mor- 



