INTESTINAL DIGESTION. 



of crystals. This was all the stercorine to be extracted from the regular, 

 daily evacuation of a healthy male twenty-six years of age and weighing about 

 one hundred and sixty pounds (72*58 kilos.). In the absence of other inves- 

 tigations, the daily quantity of this substance excreted may be assumed to be 

 not far from ten grains (0-648 gramme). 



In many regards stercorine bears a close resemblance to cholesterine. It 

 is neutral, inodorous, and insoluble in water and in a solution of potassium 

 hydrate. It is soluble in ether and in hot alcohol, but is almost insoluble in 

 cold alcohol. A red color is produced when it is treated with strong sul- 

 phuric acid. It may be easily distinguished from cholesterine, however, by 

 the form of its crystals. It fuses at a low temperature, 96'8 Fahr. (36 C.),, 

 while cholesterine fuses at 293 Fahr. (145 C.). 



Stercorine crystallizes in the form of thin, delicate needles, frequently 

 mixed with clear, rounded globules, which are probably composed of the 

 same substance in a non-crystalline form. When the crystals are of consid- 

 erable size, the borders near their ex- 

 tremities are split longitudinally for a 

 short distance. The crystals are fre- 

 quently arranged in bundles. They 

 are not to be confounded with excre- 

 tine, which crystallizes in the form 

 of regular, four-sided prisms, or with 

 the thin, rhomboidal or rectangular 

 tablets of cholesterine. They are 

 identical with the crystals of seroline, 

 figured by Robin and Verdiel. 



There can be no doubt with regard 

 to the origin of the stercorine which 

 exists in the faeces. Whenever the bile 

 is not discharged into the duodenum,, 

 as is probably the case for a time in 



FIG. 81. Stercorine from the human fceces. 



icterus accompanied with clay-colored evacuations, stercorine is not to be dis- 

 covered in the dejections. In one case of this kind, in which the fa3ces were 

 subjected to examination, the matters extracted with hot alcohol were entirely 

 dissolved by boiling for fifteen minutes with a solution of potassium hydrate, 

 showing the absence of cholesterine and stercorine. In another examination 

 of the faeces from this patient, made nineteen days after, when the icterus 

 had almost entirely disappeared and the evacuations had become normal, 

 stercorine was discovered. These facts show that the cholesterine of the 

 bile, in its passage through the intestine, is changed into stercorine. Both 

 of these substances are crystallizable, non-saponifiable, are extracted by the 

 same chemical manipulations, and behave in the same way when treated with 

 sulphuric acid. Stercorine must be regarded as a modification of cholesterine, 

 which is the excrementitious constituent of the bile. 



The change of cholesterine into stercorine is directly connected with the 

 process of intestinal digestion. If an animal be kept for some days without 



