CLOUDY SWELLING. 2^ 



lens with its cortical portion ; an opacity which remains stationary 

 for a long time, but which ultimately results in the formation of 

 <rrev cataract. 



But the non-vascular tissues do not stand alone in this respect ; 

 nearly all the tissues of the body, nay, even the vessels them- 

 selves, are liable to fatty degeneration in consequence of old age 

 and analogous conditions of debility due to exhausting diseases. 

 The muscular substance of the heart is especially subject to this 

 morbid change. 



As this, however, is not the place for an exhaustive treatment 

 of the subject, but only for a general review of it, I hasten on 

 to the last and most important — namely, the exclusively patho- 

 logical category of fatty metamorphoses. This includes all cases 

 of disproportion between the means of nutrition and the paren- 

 chyma to be nourished. Such a disproportion may be caused either 

 by a diminution of the nutriens^ or by an increase of the mitrien- 

 dum. If a minute vessel in the brain is plugged, the circulation 

 in the area which it supplies is not wholly suspended, owing to 

 the manifold anastomoses with neighbouring vessels ; neverthe- 

 less, a very considerable retardation of the current takes place, 

 which may even give rise to temporary stasis, and to haemor- 

 rhage ; and this suffices to disturb nutrition, and so to cause fatty 

 metamorphosis (yellow softening). 



The disturbance in the circulation, associated with inflam- 

 mation, exercises an influence not less hurtful upon the nutrition 

 of parts. Here, too, the amount of pabulum is inadequate. 

 Moreover, inflammation combines this with another cause of dis- 

 turbed nutrition, i.e. an increase in the amount of parenchyma 

 requiring nourishment. The mere oedema of the latter acts in 

 this way ; but the chief factor in the production of retrograde 

 metamorphosis is in this case, as in that of many tumours (e.g. 

 cancerous and tuberculous formations) the massive proliferation 

 of corpuscular elements. 



B. Cloudy Sivelling. 



% 36. We give this name to an acute swelling and granular 

 cloudiness of the protoplasmic mass, which appears to depend 

 on the precipitation of certain albuminous matters held in solu- 

 tion by the juices of the protoplasm. The change varies in 



