INTESTINAL CONCRETIONS 389 



soaps. Two intestinal concretions analyzed by Schuberg 1 had 

 the following percentage composition when dried : 



Ammonio-magnesium phosphate 57.1 63.9 



Calcium phosphate 15.7 23.8 



Calcium carbonate . . ... 4.6 



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 concre- 

 tions are not infrequent ; they contain calcium and magnesium 

 phosphate, about 70 per cent. ; oatmeal bran, 15-18 per cent. ; 

 soaps and fats, about 10 per cent. (Hammarsten). Occasion- 

 ally concretions consisting largely of fat and soaps are found, 

 and after taking large doses of olive oil masses of solidified oil 

 may be passed that are readily mistaken for softened gall-stones, 

 for the removal of which the oil is usually given. 



Bezoar stones are intestinal concretions probably coming 

 from Capra cegagrus and Antelope dorcas. One variety consists 

 chiefly of lithofellic acid, C 20 H 36 O 4 , 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, C 14 H 6 O 8 , 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/ 7 consisting of 

 particles of indigestible food, such as the sclerenchymatous 

 particles in the flesh of pears ; and (2) true sand, consisting 

 largely of inorganic material, and formed, according to Duck- 

 worth and Garrod, 2 in the upper part of the large intestine. 

 Analyses of specimens by Garrod showed the following com- 

 position : 



. . if .f 



[ traces of Mg, Fe, etc. . . . 0.47 



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 chiefly to urobilin, unaltered 

 bile-pigments being scanty. 



Preputial concretions sometimes form beneath a prepuce 

 that cannot be retracted, through deposition of urinary salts on 



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



2 Lancet, 1902 (i), 653. Full resume and literature. 



