COMPOSITION OF THE FAECES. 379 



broken up by chewing. Portions of muscular fibres, ham, tendon, 

 cartilage, particles of fat, coagulated albumin vegetable cells from 

 potatoes and vegetables, raw starch, &c. 



All food yields a certain amount of residue white bread, 3'7 p.c.; rice, 4'1 p.c.; 

 flesh, 4*7 p.c.; potatoes, 9'4p.c.; cabbage, 14*9 p.c.; black bread, 15 p.c.; yellow 

 turnip, 20 '7 p.c. (Rubner). 



(3.) The decomposition products of the bile-pigments, which do not 

 now give the Gmelin-Heintz reaction ; as well as the altered bile-acids 

 (177, 2). This reaction, however, may be obtained in pathological 

 stools, especially in those of a green colour ; unaltered bilirubin, bili- 

 verdin, glycocholic, and taurocholic acids occur in meconium (Zweifel, 

 Hoppe-Seyler). 



(4.) Unchanged mucin and nuclein the latter occasionally after a 

 diet of bread, together with cylindrical epithelium in a state of partial 

 solution, from the intestinal canal, and occasional drops of oil. 

 Cholesterin is very rare. The less the mucus is mixed with the faeces, 

 the lower the part of the intestine from which it was derived 

 (Nothnagel). 



(5.) After a milk diet and also after a fatty diet, crystalline needles 

 of lime, combined with fatty acids, chalk-soaps, constantly occur, even 

 in sucklings (Wegscheider). Even unchanged masses of casein and 

 fat occur during the milk-cure. Compounds of ammonia, with the 

 acids mentioned at p. 375, the result of putrefaction, belong to the 

 faecal matters (Brieger). 



(6.) Amongst inorganic residues, soluble salts rarely occur in the 

 faeces because they diffuse readily e.g., common salt, and the other 

 alkaline chlorides, the compounds of phosphoric acid, and some of those 

 of sulphuric acid. The insoluble compounds, of which ammoniaco- 

 magnesic or triple phosphate, neutral calcic phosphate, yellow coloured 

 lime salts, calcium carbonate, and magnesium phosphate are the chief, 

 form 70 p.c. of the ash. Some of these insoluble substances are derived 

 from the food, as lime from bones, and in part they are excreted after 

 the food has been digested, as ashes are eliminated from food which 

 has been burned. 



The excretion of inorganic substances is sometimes so great, that 

 they form incrustations around other faecal matters. Usually 

 ammoniaco-magnesic phosphate occurs in large crystals by itself, or it 

 may be mixed with magnesium phosphate. 



(7.) A considerable portion of normal faecal matter consists of 

 micrococci and microbacteria (Bacterium termo Woodward, Noth- 

 nagel). Bacillus subtilis is not very plentiful, while yeast is seldom 

 absent (Frerichs, Nothnagel). In stools that contain much starch, the 

 bacillus amylobacter, which is tinged blue with iodine, occurs (p. 374), 



