183 
Dr. Benjamin Smith Barton, a native of Pennsylvania, who had 
received his medical education at Edinburgh and Gottingen, be- 
came a professor in the University of Pennsylvania in 1790, at 
the early age of twenty-four, and continued to occupy this chair 
until his death twenty-five years later. His position gave him 
much prestige, and his contributions to the advance of American 
botany are to be measured less by his published work than by 
the influence of his botanical lectures, and the sympathy and 
financial support given by him to other students, such as Pursh 
and Nuttall. His nephew, Dr. William P. C. Barton, also be- 
came a well-known botanist. 
One of Dr. Barton’s students, whose interest in botany seems 
to have been first aroused, however, by Humphry Marshall, was 
Dr. William Baldwin. Dr. Baldwin had already visited China 
before he received his professional degree in 1807, and within the 
next ten years he traveled extensively in the southern states, and 
as a surgeon in the United States Navy visited various South 
American ports. In 1819 he joined a government expedition for 
the exploration of the upper Missouri, and died before they were 
well under way. His published papers were few, but his notes 
and memoranda were very useful to contemporary workers, and 
his memory is kept green by the publication of a volume of his 
letters by his friend, Dr. Darlington. 
Dr. William Darlington was another physician who enjoyed 
the inspiration of Barton’s lectures, and in spite of his arduous 
abors as a member of Congress and in various other public and 
semi-public positions, devoted much time throughout a long life 
to botanical study. His flora of his home county of Chester, 
which went through three editions, was a model local flora which 
in some respects has never been surpassed. He was deeply in- 
terested in such subjects as those we are discussing to-day, and 
it was through his efforts and under his editorship that the literary 
relics of Bartram, of Marshall, and of Baldwin, were rescued 
from oblivion. 
Lewis D. de Schweinitz was a Moravian preacher, a native of 
Bethlehem, Pennsylvania, where he spent most of his life. He was 
educated in part, however, in Austria and Germany ; although 
