EXCRETINE AND EXCRETOLEIC ACID. 399 



is not very great, as only 12*6 grains were obtained by 

 Marcet from nine evacuations. 1 



We have very little definite information concerning the 

 production of excretine. Marcet examined, on one occasion, 

 the contents of the small intestine of a man that had died of 

 disease of the heart, without finding any excretine. 2 It is 

 probable that this principle is formed in the large intestine, 

 though further observations are wanting on this point. 



The substance called excretoleic acid is very indefinite in 

 its composition and properties. It is described as an olive- 

 colored fatty acid, insoluble in water, non-saponifiable, and 

 very soluble in ether and in hot alcohol. It fuses at from 

 77 to 79 Fahr. 



Stercorine. This principle, which we discovered in the 

 faeces in 1862, was described by Boudet in 1833, as existing 

 in excessively minute quantity in the serum of the blood, 

 and was called by him seroline. As we found it to be the 

 most abundant and characteristic constituent of the sterco- 

 raceous matter, we proposed to call it stercorine ; 3 particu- 

 larly as our researches led us to the opinion that it really 

 does not exist in the serum, but is formed from cholesterine 

 by the processes employed for its extraction. 



Stercorine may be extracted in the following way : The 

 fseces are first evaporated to dryness, pulverized, and treated 

 with ether. The ether extract is then passed through animal 

 charcoal, fresh ether being added until the original quantity 

 of the ether extract has passed through. It is impossible to 

 decolorize the solution entirely by this process ; but it should 

 pass through perfectly clear and of a pale amber color. The 

 ether is then evaporated, and the residue extracted with boil- 

 ing alcohol. This alcoholic solution is evaporated, and the 

 residue treated with a solution of caustic potash for one or 



1 MARCET, Philosophical Transactions, 1857, p. 410. 



9 Ibid., 1854, p. 269. 



3 American Journal of the Medical Sciences, October, 1862. 



