parietal pericardium: the tough outermost layer of the pericardium that is attached to the diaphragm and the sternum
serous membrane: a thin membrane lining the closed cavities of the body; has two layers with a space between that is filled with serous fluid
lichen: any thallophytic plant of the division Lichenes; occur as crusty patches or bushy growths on tree trunks or rocks or bare ground etc.