Leonardo Botalli, a Piedmontese physician, born at Asti about 1530. He was educated at Pavia, and went to France in 1561, where he acquired celebrity by his controversies with the faculty of Paris on the subject of bloodletting. In 1571 he was appointed physician in ordinary to Elizabeth, queen of Charles IX., and afterward to Catharine de' Medici. He wrote a number of important medical works, including De Catarrho, De Lue Venerea, De Curan-dis Vulneribus Sclopetorum, De Via Sanguinis a Dextro in Sinistrum Cordis Ventriculum, and De Curatione per Sanguinis Missionem. His chief claim to distinction at present rests upon a singular error, namely, the description in the fourth of the works enumerated above of an exceptional case in which the foramen ovale, between the right and left auricles of the heart, remained open in the adult. Botalli supposed this to be a normal appearance, and described it accordingly as a natural opening, giving passage to the arterial blood into the left auricle; while in reality it exists, as a general rule, only in the foetus, and when present in the adult does not allow the blood to pass through it.

It is still known, however, as the u foramen of Botal".