152 SOME AMERICAN MEDICAL BOTANISTS 



phia in 1829, he had a strong bent towards natural 

 science, very soon being appointed one of the 

 curators at the Academy of Natural Sciences, and 

 during this time publishing a brief essay on The 

 Geographical Distribution and Leading Charac- 

 ters of the United States Flora. 



When the United States Exploring Expedition 

 was organized in the autumn of 1838 to sail for 

 the South Seas, Pickering was elected as the prin- 

 cipal zoologist, and the fame of that expedition 

 rests chiefly on the work he then did with Pro- 

 fessor Dana. Although Pickering retained the 

 ichthyology, he went keenly into the geograph- 

 ical distribution of animals and plants; to the 

 latter especially, as affected by the operations 

 and movements of the races of man. A year 

 after the expedition, and at his own expense, he 

 visited Egypt, Arabia, Eastern Africa and West- 

 ern and Northern India, publishing in 1848 his 

 volume The Races of Men and their Geograph- 

 ical Distribution (vol. ix, Wilkes Exploring 

 Expedition Report}. In the fifteenth volume 

 appeared his Geographical Distribution of Ani- 

 mals and Plants. He had no better luck than 

 many a scientist; for, in the course of printing, 

 Congressional appropriations stopped, and the 

 publication of further Reports was abandoned. 

 But, under privilege, he brought out in 1854 a 

 small edition of the first part of his essay, and in 



