YELLOSO, Jose Mariano da Conceicao (vail-lo-so), Brazilian scientist, born in Rio das Mortes in 1742; died in Rio Janeiro in 1811. After studying in his native province, he was sent to Rio Janeiro, where he finished his education in the convent of Sao Boaventura in 1761, and entered the order the next year. He then began the study of philosophy in the convent of Santo Antonio, and in 1766 was graduated as Ph. D., and received sacred orders. In 1768 he was sent as preacher to Sao Paulo, in which city he was appointed in 1771 professor of geometry, and obtained the chairs of rhetoric in 1779 and natural history in 1786. Soon the viceroy, Luiz de Vasconcellos, called him to Rio Janeiro and commissioned him, with Francisco Solano, to make a botanical exploration of the province. After many years of work he finished in 1790 his celebrated work on the flora of the province of Rio Janeiro, which contained alone 1,640 plants of new and formerly unclassified species. The viceroy ordered him to present his work personally at court in Lisbon, where the manuscript was lost in the archives, but it was discovered in 1824 in the royal library by Antonio de Arrabida, and the Emperor Pedro I. obtained a copy, which was published by his orders. Velloso was honored in Lisbon with the friendship of the prince regent, and by him appointed director of the topography of the "Arco do Cego," which in 1798 was incorporated in the royal printing-office. Velloso continued as one of the directors, was a corresponding member of the Royal academy of science and many other scientific societies, and provincial of his order, but, desiring to return to his country, he was in 1809 nominated superior of the convent of Santo Antonio in Rio Janeiro, where he died two years after. A plant of the Euphorbiae family has been named in his honor Vellosia jabanesia princeps. He wrote " O Fazendeiro do Brazil," a work on agriculture (11 vols., Lisbon, 1794); "Ornothologia Brazileira, ou enumeraao de muitas ayes uteis" (1804) ; "Estudo sobre a cochonilha" (1807) ; "Sobre e Lavrador pratico, contendo a historia da canna de assucar" (Rio Janeiro, 1810); and a great natural history, "Flora Fluminense, ou descripao das plantas que nascem espontaneas no Rio de Janeiro" (11 vols., 1825).