Fig. (2) (A) Tombstones in the Old Jewish Cemetery (Venice, Italy). Grey discoloration of limestone (Istrian stone) due to colonization by black meristematic fungi. (B) Cross section stained by PAS. (C) Resin casts showing the fungal distribution pattern (bar = 0.1 mm). (D) Detail of endolithic hyphae (bar = 20µm). (E) Micrograph of fresh slide of the black meristematic fungus colonizing the stone.