Jan Constantijn Costerus

Jan Constantijn Costerus (29 March 1849 – 31 July 1938) was a Dutch biologist who specialized in teratology or studies on mutations in plants.

A contemporary of Hugo de Vries, he also founded of a botanical garden in Hilversum.

While still a student he read a Dutch translation of Darwin's theory of natural selection.

Costerus and his fellow student Nicolaas Dirk Doedes (1850–1906) wrote a letter to Darwin and received a reply.

On his death in 1938 he bequeathed a sum of 1000 guilders to cover the maintenance of the garden to the Hilversum municipality.