OR GAZELLES. 441 



To obtain a clear idea of thefe concretions, 

 they muft be diftributed into feveral dalles, re- 

 ferring to the animals which produce them, and 

 the climates and food that are favourable to their 

 production. 



1. The ftones formed in the bladder and kid- 

 neys of men and other animals mud be fepa- 

 rated from the clafs of bezoars, and denominated 

 by the appellation of calculi, their fubftance be- 

 ing totally different from that of the bezoars. 

 They are eafily diitinguifhed by their weight, 

 their urinous odour, and their ltru&ure, which 

 is neither regular, nor compofed of thin con- 

 centric circles, like that of the bezoars. 



2. The concretions fometimes found in the 

 gall-bladder and liver of men and animals ihould 

 not be regarded as bezoars. They may be di- 

 ftinguifhed by their lightnefs, their colour, and 

 their inflammability ; befides, they are not form- 

 ed of concentric circles round a nucleus. 



3. The balls frequently found in the ftomachs 

 of animals,and efpeciallyof the ruminating kinds, 

 are not true bezoars. Thefe balls, which are 

 called JEgagropili, are compofed, internally, of 

 hairs fwallowed by the animal, when licking ltfelf, 

 or of hard roots which it was unable to digeft ; 

 and, externally, moft of them are covered with 

 a vifcid fubftance, which has fome refemblance 

 to bezoar. Hence the aegagropili have nothing 

 in common with the bezoars but this external 



Vol. VI. F f covering ; 



