This specimen has also been known as Pithecanthropus 1. In Indonesia, the fossil is known as "Pithecanthropus modjokertensis". One of von Koenigswald's assistants brought him a piece of a "Pithecanthropus" skull in 1937. One skull cap, the first Sangiran calvarium, was an exact duplicate of Dubois' "Pithecanthropus calvarium". Pithecanthropus Erectus is a 1956 album by jazz composer and bassist Charles Mingus. He even formally named this missing link "Pithecanthropus alalus", translated as "ape man without speech". He called his finds "Pithecanthropus erectus" ("ape-human that stands upright") or Java Man. Later, Pithecanthropus was incorporated into the genus "Homo" as "Homo erectus". "Pithecanthropus" is a genus that German biologist Ernst Haeckel (1834-1919) had created in 1868. "Pithecanthropus" is now classed as "Homo erectus", thus a junior synonym of "Homo".