"Excubias habent grues nocturnis temporibus lapillum pede sustinentes, qui laxatus somno et decidens indiligentiam coarguat. Ceterae dormiunt, capite subter alam condito alternis pedibus insistente."
Naturalis historia 10,30
Pliny the Elder, Gaius Plinius Secundus, born 23 A.D. in Como - died 79 A.D. in Stabiae (today Castellammare di Stabia) when Mount Vesuvius erupted; writer, uncle and adoptive father of Pliny the Younger
"During the night, also, they place sentinels on guard, each of which holds a little stone in its claw: if the bird should happen to fall asleep, the claw becomes relaxed, and the stone falls to the ground, and so convicts it of neglect. The rest sleep in the meanwhile, with the head beneath the wing, standing first on one leg and then on the other."
(Translation: John Bostock, 1855)
Based on this legend as we read it in Pliny"s Natural History and also in the works of Aesopius, the crane holding a stone in its claw came to be a symbol of watchful care in Antiquity and the Middle Ages. In the mid-19th century, the crane serves as a motif on the seal used by the Mendelssohn bankers. Reinforced by the family motto "Ich wach" (I am keeping watch), the family used the crane as the heraldic animal in their coat of arms following their ennoblement in 1888. It can be found on artifacts owned by the Mendelssohn family such as bookplates, gravestones, painted on window glazing and engraved into the base of a baptismal bowl.
Today, the Mendelssohn-Gesellschaft uses the emblem to symbolize the family"s legacy of exercising civic responsibility.