"All birds are divided as between those which are of passage, like swallows and cranes, and those which are domestic, like chickens and pigeons: thrushes are birds of passage and every year fly from across the sea into Italy about the time of the autumn equinox, returning about the spring equinox.

Thrush is a disease of the follicles of the mucous membrane of the alimentary canal, whereby there are formed small vesicles, or bladders, filled with a thick mucous secretion, which, bursting, discharge their contents, and form minute ulcers in the centre of each vessel.