INTESTINAL CONCRETIONS 467 



calcium and magnesium soaps. Two intestinal concretions analyzed by Schuberg" 

 had the following percentage composition when dried : 



Ammonio-magnesiuni phosphate 57. 1 63.9 



Calcium i)hosphate If).? 23.8 



Calcium carbonate 4.0 



Calcium sulphate 3.0 0.7 



Alcohol-ether extract 1.9 0.8 



Other organic substances 21 .5 6.0 



In countries where oatmeal is largely eaten, intestinal concretions are not infre- 

 quent; they contain calcium and magnesium phosphate, about 70 per cent.; 

 oatmeal bran, 15-lS per cent.; soaps and fats, about 10 per cent. (Hammarsten). 

 Occasionally concretions consisting largely of fats and soaps are found, and after 

 taking large doses of olive oil masses of solidified oil may be pa.ssed that are readily 

 mistaken for softened gall-stones, for the removal of which the oil is usually given. 

 The "fecal stones" found in appendices often show the structure of calculi, and, 

 unlike other enteroliths, consist less of ammonio-magnesium phosphate than of 

 calcium salts i^" soaps may be important constituents.''^ 



Bezoar stones are intestinal concretions probably coming from Capra aegngrus 

 and Antelope dorcas. One variety consists chiefly of lithofellic acid, C2nH.-)fi04, which 

 is related to cholalic acid, and gives an aromatic odor when heated. The other 

 variety ("false bezoars") does not give the aromatic odor, and consists chiefly 

 of ellagic acid, Ci4H60s, a derivative of gallic acid, and, therefore, probably derived 

 from the tannin of the food of the antelopes. 



Intestinal "sand" occurs as (1) "false sand," consisting of particles of indi- 

 gestible food, such as the sclerenchymatous particles in the flesh of pears and 

 bananas;" and (2) true sand, consisting largely of inorganic material, and formed, 

 according to Duckworth and Garrod,^-^ in the upper part of the large intestine. 

 Analyses of specimens by Garrod showed the following composition: 



Water 12.4 f calcium oxide 54 . 98 



Organic material 26.29 I phosphorus pentoxide 42.35 



Inorganic material. . . 61 31 containing | carbon dioxide 2.20 



[ traces of Mg, Fe, etc . 47 



Analyses by other observers have given similar results, the absence of the large 

 proportion of magnesium found in larger concretions being striking. The color 

 is usually brown, due chieflj^ to urobilin, unaltered bile-pigments being scanty. 



Preputial concretions sometimes form beneath a prepuce that cannot be 

 retracted, through deposition of urinary salts on and in the accumulated smegma. ^^ 

 The composition is, therefore, very mixed, and consists of an organic base contain- 

 ing much cholesterol, fats, and soaps, incrusted with inorganic substances, of 

 which ammonio-magnesium phosphate and calcium phosphate are usually the 

 most abundant. 



Prostatic concretions originate in the corpora amylacea through growth ac- 

 cretion of inorganic salts, until they may reach considerable size. Stern^' gives 

 the following results of analysis of such a prostatic stone: 



Water 8.0 



Organic matter. . . 15.8 



Lime ' 37 . 64 



Magnesia 2 . 38 



Soda 1 . 76 



Potash 0.5 



Phosphoric acid 33 . 77 



Iron trace 



'9 Virchow's Arch., 1882 (90), 73. 



*° Harlay, Jour, pharm. et chim., 1910 (2), 433. 



^' Williams, Biochem. Jour., 1907 (2), 395. 



" Myer and Cook, Amer. Jour. Med. Sci., 1909 (137), 383. 



•"■^ Lancet, 1902 (i), 653. Full resume and literature. 



" See Zeller, Arch. klin. Chir., 1890 (41), 240. 



« Amer. Jour. Med. Sci., 1903 (126), 281. 



