MUCOUS SYSTEM. 



Q. What is remarkable of the properties alluded to in 

 the last answer? 



*/?. That they are liable to higher degrees and greater 

 varieties of exaltation than in other tissues. From this fact 

 results the consequence that these tissues are subject to a 

 variety of diseases. 



Q. How does Bichat divide the sympathies of this tex- 

 ture? 



t/tf. Into active and passive. In the first it influences 

 other parts; in the second it is influenced by those parts. 



Q. Repeat the general law of sympathies, which we 

 have more than once alluded to. 



/?. That they act on the predominant vital properties 

 of a part; for instance, exciting animal sensibility where 

 that predominates, or animal contractility, or sensible or- 

 ganic contractility, according as the one or other may be 

 the principal vital property. 



Q. It is important to recollect the active sympathies of 

 the mucous surfaces, will you give illustrations of them? 



*/2. Irritation on the pituitary membrane excites the 

 animal contractility of the diaphragm to sneezing. 

 ftnimal sensibility is excited sympathetically at the glans 

 penis, by a stone irritating the mucous membrane of the 

 bladder; the same vital property is in action when worms 

 in the intestines induces itching at the nose. The semen 

 passing the urethra, excites the sensible organic contrac- 

 tility of the heart to increased action; the same vital pro- 

 perty in the stomach is exalted in the vomiting occasion- 

 ed by the irritation of a stone on the lining membrane of 

 the pelvis of the kidney. You see a sympathetic excite- 

 ment of organic sensibility and insensible organic con- 



