DEGENERATIONS AND INFILTRATIONS. 



277 



degeneration. Serous infiltration, more or less complicated with 

 albuminoid degeneration, also occurs in inflammations when the 

 serous constituent of the exudate is prominent. 



6. Mucous Degeneration. This form of degeneration has its nor- 

 mal analogue in the elaboration of mucus by the epithelial cells 

 covering many of the mucous membranes or lining mucous glands. 



FIG. 250. 



Vaciiolation of striated muscle. (Volkmann.) The specimen is from the rectus abdominis 

 muscle from a case of typhoid fever. The cross-sections of the muscle-fibres contain spaces 

 within the contractile substance, which are filled with a clear, fluid serum. The fibres 

 so infiltrated are larger than those containing no such vacuoles. The cavities are, therefore, 

 not produced at the expense of the contractile substance. Between the fibres is the in- 

 termuscular, vascularized fibrous tissue, forming the interstitial tissue of the muscu- 

 lar organ. 



But the elaboration of mucin is not confined to epithelium. It may 

 be produced by the cells of the connective tissues, appearing among 

 the intercellular substances. This is most marked in mucous tissue, 

 where the general character of the tissue is determined by the 

 mucus in the intercellular substance. There is also a comparatively 

 small amount of mucus in other forms of connective tissue, espe- 

 cially in the fibrous varieties. 



Under morbid conditions, which \ve are not able exactly to define, 

 this production of mucus is increased. In epithelial and other cells 



