861. The first systematic work upon the flora of North America appeared in 1803, from the pen of Andre Michaux, under the title of Flora Boreali-Americana. Partial floras had been previously published by Walter, Clayton, Gronovius, and others ; but the most extensive appeared in 1816, by F. Pursh, a Prussian botanist, who spent nearly twelve years beyond the Atlantic in botanic travel, and in the management of two botanic gardens ; the last that of Elgin. From the preface to this Work we are enabled to give the names of the principal botanic gardens in the United States. In British America there are none. The first gardens Pursh saw were the old established gardens of M. Marshall, author of a small treatise on the forest trees of North America. These were rather on the decline. The botanic garden of J. and W. Bartram, on the banks of the Delaware, near Philadelphia (now Carr's nursery), was founded by their father under the patronage of Dr. Fothergill. The garden of the American patriot, Hamilton, was in his time one of the richest in plants in America. Those of Dr. Hosack, Mr. Pratt, Mr. Fox, Dr. Wray, Mr. Oemler, Mr. Young, and M. Le Conte, were also all celebrated for their botanical riches. (See Gard. Mag., vol. viii. p. 27.)