his life there were old friends to whose families he was the only acceptable medical adviser and whose appeal for aid he could not refuse. Illustrating this fact, as well as Engelmann's energetic manner, his son relates the following incident: “It was a bitter, sleety winter night, when the ringing of the doorbell awoke me, and I heard an urgent call for father from the messenger of a patient. I would not arouse him, and proposed to go myself; but he had heard all, and, hurrying into his clothes, was ready to go in spite of my remonstrance 'What of the night?' he said, vexed at my interference, 'Am I already useless, to be cast aside? I would rather die in harness than rust out.' So I helped him down the icy steps, through the blinding sleet, into his carriage, and off on his mission of mercy.” Botanical studies Engelmann devoted himself to his medical practice, but in his later years made a specialty of botany. An 1842 monograph on dodders, a very difficult genus to examine, had established his reputation as a botanist. He took several vacations from his medical practice and devoted them all to the gathering of data for his scientific work, the details of which were elaborated at his home. One of these vacations extended from 1856 to 1858, the greater part of the first summer having been spent in botanical work at the Harvard gardens and herbarium in companionship with Asa Gray. Then, with his wife and young son, he visited his native land and other parts of Europe, occupying his time with scientific observation and study. In 1868 Dr. Engelmann and his wife again visited Europe for a year, the son being then in Berlin pursuing his medical studies. These visits to Europe were also the occasions of frequent and familiar personal interviews with men whose names were well known to the scientific world, such as Joseph Dalton Hooker, Alexander Braun, De Bary, Virchow, and others. In 1859, he published Cactaceae of the Boundary which studied cacti on the border of the United States and Mexico. He also made special studies of the pines, rushes, spurges, and other little-known and difficult groups, contributing numerous articles on them to the St. Louis Academy of Sciences, to the American Academy of Arts and Sciences, and to government reports. Material in his specialties collected by the federal