In connection with pericarditis it is not very uncommon to meet with calcareous infiltration of old fibrine or dried-in pus which may remain on the surface. Again, where, in the pericardium, there has been great new-formation of dense connective tissue from prolonged pericarditis, lime salts may be deposited in the hard tissue. In this way we may have the heart almost enclosed in a firm shell. But, further, in the .muscular substance, old cicatrices may calcify, or an abscess may dry-in and become impregnated with lime salts. In this way we may have stony masses developed in the muscular wall, these being actually in the connective tissue of the wall. Of much greater frequency and importance is the deposition of lime salts in the valvular structures. This is usually a result of the changes occurring in chronic endocarditis (which see), but we meet with considerable calcification, especially in old persons, without much thickening.