Infrastructural and Crystallographic Study of Experimental Calcifications 165 



treated according to Gabriel is transformed into apatite which can be identified by 

 X-ray diffraction. 



convoluted tubule. 



Discussion 



The morphological arrangement of calcium salt depositions vanes to a great 

 extent according to their crystallographic form. Various explanations are given con- 

 cerning the conditions governing the different forms of crystallisation: local pH 

 value, presence of mucopolysaccharides, function of a particular segment of the 

 nephron in the case of the kidney. It will be noted that in the kidney at least, the 



