The inorganic materials of nerve-cells are Magnes. phos., Kali phos., Natrum and Ferrum. Muscle-cells contain the same, with the addition of Kali mur. Conneclive tissue-cells have for their specific substance Silicea, while that of the elastic tissue-cells is probably Calc. fluor. In bone-cells we have Calc. fluor. and Magnes. phos. and a large proportion of Calc. phos. This tatter is found in small quantities in the cells of muscle, nerve, brain and connective tissue. Cartilage and mucous cells have for their specific inorganic material Natr. mur,, which is found also in all solid and fluid parts of the 'body. Hair and the crystalline lens contain, among other inorganic substances, also Ferrum. The carbonates, as such, are, according to Moleschott, without any influence in the process of cell-formation.