Nettie M. Stevens (1862-1912) passed away on May 4th, 1912 at the age of fifty. She was born in Connecticut and graduated from Vassar College when she was 23. After completing her undergraduate degree, she pursued a doctorate degree in biology from Bryn Mawr College, where she was also the first woman to receive a Ph.D. in zoology. As a scientist, her most outstanding work involved research on chromosomal sex determination. Her work would become the foundation of the modern understanding on sex linkage and the basis of genetic inheritance and through it she identified the mechanisms underlying sex differences in genetic inheritance. Nettie was an accomplished scientist and a loved professor at Bryn Mawr, where she taught zoology, genetics and other natural sciences until her passing. She will be remembered by her students and colleagues who she has inspired over the years. Those who knew Nettie will remember with fondness her intelligence, tenacity, and hard work. Her contributions to the scientific community will not be forgotten. She will be greatly missed.