Contributions of Wilhelm His to Human Embryology [Contribuciones de Wilhelm His a la Embriología Humana]

Wilhelm His (1831-1904), a great Swiss anatomist and embryologist, professor of anatomy at the university of Basel and the university of Leipzig. His, made the first attempt to study the different stages of the total human embryo. For that purpose he introduced important technological advances that allowed a more detailed understanding of the embryo, setting a landmark in the development of embryology as a science. This paper summarizes the main contributions of Wilhelm His in the field of human embryology. One of his major contributions was the invention of the microtome en 1866, which allowed the reconstruction of the embryo from histological sections. Another one of his great inventions was the so-called embryograph, an instrument that allows viewing histological sections at low magnification and reconstructing them on paper. He was also a pioneer in attempting to select human embryos presumably collected in their order of development. He divided human development into stages, establishing standards from the relations between the shape and size characteristic of each stage. A large part of his discoveries on the development of the human embryo is found in his work titled Anatomie der Menschlichen Embryonen (1880-1885). The noble task of elucidating the anatomy of the human embryo was possible thanks to a set of technologicals and methodological innovations and his persevering work. Because of his great contributions in the field of embryology he is given the name of "Vesalius of human embryology".