INTESTINAL CONCRETIONS. 255 



fied layers of earthy and animal matter exist. (Jirardin 



found in one 



Ammonio-phosphate of magnesia . 48 '00 



Phosphate of lime . . 19'00 



Water . . 14-00 



Animal matter -80 



Soluble salts, &c. . . 6 '60 



Extractive matters 4 '00 



Fatty matter 7'00 



Loss -60 



100-00 



In millers' horses the second form has been frequently 

 found, and is composed almost entirely of the beard of the 

 oat or barley firmly matted together, and disposed in concen- 

 tric layers, with the admixture of mucous and some excre- 

 mentitial materials. These are the dust balls or oat-hair 

 concretions which sometimes attain great size. 



The mixed calculi contain dung, phosphatic salts, mucous, 

 oat hairs, and any indigestible or agglutinating material, 

 which may surround any solid object which may accidentally 

 float in the intestine. 



An interesting case of calculus in the horse's intestine is 

 reported by Mr Maclaren Kitching, in the first volume of the 

 Edinburgh Veterinary Review. The calculus is in the New 

 Veterinary College Museum. It is irregularly spherical and 

 nodulated; two pounds nine ounces in weight, and five inches 

 and a half in diameter. Its external characters are those of 

 an ordinary oat-hair calculus, with a phosphatic one imbed- 

 ded deeply in it. (See Fig. 101.) 



The small calculus a, at the lower part, is of the mixed 

 kind, and appears to have formed round a stone. This is a 



