44 GENERAL HISTOLOGY. 



as tuberculosis, all the liver cells may become filled, and the 

 bounds of the acini effaced. 



5. Calcification is the infiltration of tissue with granules or 

 crystals of calcium, or of alkaline salts. Free carbonic acid 

 is a solvent of these salts, and, by its capacity for diffusion, it 

 escapes, leaving insoluble salts in the nutritive fluid. True 

 osseous tissue differs from calcification by the intimate union 

 of glutinous and calcium elements, and the vital modification 

 of molecular coalescence into the concentric lamella? of bone 

 structure. Calcification of arteries is a secondary affection, 

 following fatty degeneration of the connective tissue. Ar- 

 thritic deposit of u rates in gouty persons is most common in 

 cartilage cells. 



4.. Degenerative Metamorphosis. 



i. Fatty degeneration is a metamorphosis of the protoplasm 

 or of formed material, marked by molecular fat globules. Its 

 progress may be illustrated by the degeneration of epithelial 

 cells of internal organs. Their molecules change into fat, and 

 they become granular globules, known formerly as "inflam- 

 matory" or "exudation corpuscles," or " corpuscles of Gluge." 

 They are identical with colostrum corpuscles thrown off from 

 the mammary gland after parturition. These globules disin- 

 tegrate to a fatty detritus, and the last act of fatty degenera- 

 tion is lactification. The fatty detritus may be absorbed as 

 milk. If not absorbed it is partly saponified and partly sep- 

 arated in solid form, as margarin, etc. Finally there is a de- 

 posit of crystals of cholesterin, which crystallizes in rhombic 

 tablets, with their long sides parallel. In some cases, when 

 the fatty matter is not absorbed, it undergoes a change into a 

 crumbling material resembling cheese, and the process i* 

 called cascation. It was formerly regarded as the result of 

 tuberculosis, and considered as the separation of morbid mat- 

 ter, or crude tubercle, from the blood. Tubercle may un- 

 dergo fatty degeneration and caseation, but all cheesy matters 

 are not tubercular. Such masses in the lungs were consid- 

 ered to be inspissated pus, but Virchow and others show them 

 to be the product of fatty degeneration, with but little water 

 present. Sometimes calcification occurs in such masses. 



