Mary Anning (1799-1847)
Anning was the greatest fossil hunter ever. She excavated and catalogued countless specimens from her home in Dorset, boldly facing strenuous and dangerous working conditions. Unfortunately, her male contemporaries were freaked out that a working class woman was undeniably the world's greatest paleontologist, and they prevented her from ever receiving due notice in her lifetime.
Interesting tidbit: the tongue-twister "she sells sea shells by the sea shore" was inspired by Anning's massive collection of fossils, which she sold to support her family.