Final answer:
Margaret Floy Washburn was the first woman to receive a PhD in psychology, while Harvard University declined to give Mary Calkins the PhD.
Step-by-step explanation:
Margaret Floy Washburn was the first woman to receive a PhD in psychology. In 1894, she became the first woman awarded the doctoral degree in psychology. On the other hand, Mary Whiton Calkins completed all requirements toward the PhD in psychology, but Harvard University declined to give her the PhD because she was a woman. Although Calkins made significant contributions to the field, she was not officially recognized by Harvard with the PhD.