is an extinct genus of large flightless bird that lived during the late Paleocene and Eocene epochs of the Cenozoic. It was named in 1855, after Gaston Planté, who had discovered the first fossils in Argile Plastique formation deposits at Meudon near Paris (France). At that time, Planté (described as a "studious young man full of zeal") was at the start of his academic career, and his remarkable discovery was soon to be overshadowed by his subsequent achievements in physics.
In the 1870s, the famous American paleontologist Edward Drinker Cope discovered another, more complete set of fossils in North America, and named them Diatryma ( /ˌdaɪ.əˈtraɪmə/ DY-ə-TRY-mə, from Ancient Greek διάτρημα, diatrema, meaning "canoe").
The fossil remains of these birds have been found in western-central Europe (England, Belgium, France and Germany).