CLASSIFICATION OF SECRETIONS. 37 



posed of fluid with cells and occasionally closed vesicles. 

 These are sometimes called blood-glands, because they are 

 supposed to modify the blood as it passes through their 

 substance. 



The testicles and the ovaries are not simple glandular 

 organs; for in addition to the production of mucous or 

 watery secretions, their principal function is to develop cer- 

 tain anatomical elements, the spermatozoids and the ova. 

 The physiology of these organs will be considered in connec- 

 tion with the subject of generation. 



Classification of the Secreted Fluids. The products of 

 the various glands may be divided, according to their function, 

 into secretions and excretions. The secreted fluids may be 

 subdivided into the permanent secretions, which have a more 

 or less mechanical function, and transitory secretions ; some 

 of the latter, like mucus, are thrown off in small quantity, 

 without being actually excrementitious ; others, like most 

 of the digestive fluids, are produced intermittently and 

 rapidly, and finally undergo resorption. 



Tabular View of the Secreted Fluids. 



SECRETIONS PBOPEB. 



Permanent Fluids. 

 Serous fluids. 

 Synovial fluid. 

 Aqueous humor of the eye. 

 Vitreous humor of the eye. 

 Fluid of the labyrinth of the internal ear. 

 Cephalo-rachidian, or subarachnoid fluid. 



Transitory Fluids. 

 Mucus, in many varieties. 

 Sebaceous matter. 



Cerumen, the waxy secretion of the external meatus. 

 Meibomian fluid. 

 Milk and colostrum. 

 Tears. 

 Saliva. 



