40 NUTRITION DEPENDS ON THE 



quantity of the menstrual discharge ; and when it is 

 suppressed in consequence of disease, tlie vegetative 

 life is manifested in a morl3id production of fat. 

 When the equilibrium between the vegetative and 

 nervous life is disturbed in the male, when, as in 

 eunuchs, the intensitv of the latter is diminished, 

 the predominance of the former is shewn in the 

 same form, in an increased deposit of fat. 



VIII. If we hold, that increase of mass in the 

 animal body, the developement of its organs, and 

 the supply of waste, — that all this is dependant on 

 the blood, that is, on the ingredients of the blood, 

 then only those substances can properly be called 

 nutritious or considered as food which are capable 

 of conversion into blood. To determine, therefore, 

 what substances are capable of affording nourish- 

 ment, it is only necessary to ascertain the composi- 

 tion of the food, and to compare it with that of the 

 ingredients of the blood. 



Two substances require especial consideration as 

 the chief ingredients of the blood ; one of these 

 separates immediately from the blood when with- 

 drawn from the circulation. It is well known that 

 in this case blood coagulates, and separates into a 

 yellowish liquid, the serum of the blood, and a gela- 

 tinous mass, which adheres to a rod or stick in soft, 

 elastic fibres, when coagulating blood is briskly 

 stirred. This is the fihrine of the blood, which is 

 identical in all its properties with muscular fibre, 



