208 THE FECES. 



hydrobilirubin is a laboratory product, and is met with neither in 

 the feces nor the urhic. 



Excretin. This is a substance which was first isolated by 

 Marcet from the feces of herbivorous animals, but is said to occur 

 also in human stools. According to Hinterberger, it has the formula 

 C^HggO, and is thus closely related to cholesterin. 



Stercorin. Stercorin, or aerolm, as it has been called, is a sub- 

 stance which Flint obtained from the feces of man, but which is 

 probably an impure form of cholesterin, both having the same 

 general reactions. 



MECONIUM. 



The term meconium has been applied to the material which accu- 

 mulates in the intestinal tract during foetal life, and which is expelled 

 soon after birth. Food-products are here, of course, wanting, and 

 as the intestinal tract of the foetus is free from bacteria the meconium 

 consists essentially of mucus, desquamated epithelial cells, and the 

 normal biliary constituents which are present in the intestinal tract 

 before birth. We accordingly find bilirubin and biliverdin, the 

 former often in crystalline form, the native biliary acids, a small 

 amount of fatty acids, cholesterin, and mineral salts, while hydro- 

 bilirubin, the dyslysins, leucin, tyrosin, indol, skatol, lactic acid, 

 albumoses, etc., are absent. According to Zweifel, it contains from 

 79.8 to 80.5 per cent, of water and from 19.5 to 20.2 per cent, of 

 solids, of which 0.978 is referable to mineral ash, 0.797 to choles- 

 terin, and 0.772 to fatty acids. 



Its color is a dark brownish -green, and the reaction usually acid. 

 In general appearance it resembles pitch, and is hence also spoken 

 of by the Germans as Kindspech (infant pitch). 



