RAMON Y CAJAL SANTIAGO Spanish histologist, was born May 1, 1852, at Petilla de Aragon (Pam plona). He graduated at the University of Saragossa, and went in 1881 as professor to the University of Valencia, and in 1886 to Barcelona, publishing in 1889 his first important work (Elementos de Histologia normal y de Tecnica Microgrdfica). In that year he discovered "the laws which govern the morphology and the con nections of the nerve cells in the grey substance." In 1890 and 1891 he discovered the primary changes of the neurin, and the genetic unity of the nerve fibres and the protoplasmic appendices. During this period also he discovered the axis cylinder of the fibres of the cerebellum and their continuity with the parallel fibrillae of the molecular covering, formulated the principle of the dynamic polarisation of the neurins, aided by Van Gehuchten, and worked upon the analysis of the sympathetic ganglia. In 1892 he took the chair of normal histology and pathological anatomy in the University of Madrid. In 1894, on the invitation of the Royal
Society of London, he developed systematically his views on morphology and connections of the nervous cells of the spinal medulla, ganglions, cerebellum, retina and olfactory bulb. He was called upon by the Clark University (Worcester) in 1899 to give an exposition of his investigations regarding the cerebral tegumen, and in 190o the International Congress of Medicine, which met in Paris, gave him the Moscow International Award. He was awarded half the Nobel Prize for medicine in 1906. His work in three volumes, Histologia del Sistema Nervioso de Hombre y de los Vertebrados, appeared between the years 1897 and 1904. In May 1922 he was exempted, on account of long service, from his duties in connection with the chair which he held, and, on the initiative of the Government, he founded the Cajal Institute in Madrid.