286 OP THE SECRETIONS JN GENERAL. 



nearly similar, also, is the fluid of the pericardium and 

 of the ventricles of the brain. 



The liquor amnii of pregnancy, and the urine, re- 

 markable for the peculiar nature and mixture of its 

 proper constituents, are generally enumerated among 

 these. 



The salivary fluids, concerned in mastication, diges- 

 tion, and chylification, appear more elaborated. 



Next the mucous, which line the cavities of most of 

 the organs performing the natural and genital func- 

 tions, and likewise the tract of the nostrils, larynx, and 

 trachea. 



The mucus within the eye, and under the epidermis, 

 is nearly similar. 



In the same class may be included the cerumen of 

 the ears, the unguent of the Meibomian glands and of 

 the joints, and, perhaps, the nameless fluid poured forth 

 into the vagina during the venereal oestrum. 



The adipose are, besides the common fat, the medulla 

 of the bones and grease of the skin. 



Related to these are the secretion of the corona 

 glandis under the preputium, and of the external female 

 genitals. 



The truly serous, or albuminous, are the fluid of the 

 ovarian vesicles of De Graaf, and the liquor of the 

 prostate. 



The semen virile and the bile are each sui generis. (A) 



468. It is obvious that so great a variety of secreted 

 fluids cannot be secreted from the mass of blood in the 

 same way, nor by similar organs. They differ ex- 

 tremely from each other in the simplicity or complexity 

 of their preparation. 



469. The most simple mode of secretion is diape- 



