Rafinesque (Oct 22, 1783 – Sept. 18, 1840) was a naturalist, traveler, and writer who made major and controversial contributions to botany and ichthyology. Rafinesque believed that each variety of a species is a "deviant," which, through reproduction, may become a permanent species; thus, he anticipated, to some extent, part of Charles Darwin's theory of evolution.
Although Rafinesque's scientific abilities were recognized in his lifetime, he was also severely criticized for sometimes doing careless work and for his tendency to establish new genera and species. Throughout his life he traveled extensively, collected specimens wherever he went, and wrote and published constantly. From Today In Science History
Image and more info here.