Museum. A little later came John Bartram who brought to his garden near Philadelphia many plants from the wilds of the southern states, over which he collected extensively. His garden with its quaint old house has appropriately been reserved for a park in which some of the memorials of his labors are still growing. Peter Kalm, whose memory is embalmed in Kalmia, the mountain laurel, was sent on a mission from Sweden primarily to investigate the American mulberry in the vain hope that Sweden might have an opportunity to compete with France in the silk industry. Kalm traveled through Pennsylvania, New York and Canada in 1748–51 and took back many plants which served as the originals of some of Linnæus' descriptions. Near the time of our revolution another acute observer lived in New York, Cadwallader Colden by name, and once lieutenant governor of the province. Colden was also one of the correspondents of Linnæus, and a list of his plants was published from Upsala. But the real commencement of our botanical exploration began with two foreign botanists, who came to this country near the close of the eighteenth century, and a third at a little later period. These were Frederick Pursh and Andre Michaux, and later Thomas Nuttall. Michaux was sent from France to collect living plants for ornamental purposes, and as the result of his exploration took back to his native country more than sixty thousand woody plants. In 1793 he crossed the then wilderness of the Alleghanies into Ohio, going down the river as far as Louisville. Two years later he went farther and pushed up the Wabash to old Vincennes, crossed Illinois to the Mississippi, which he descended as far as the mouth of the Ohio, and then up the Cumberland and across to Charleston; he also went into Florida, then wholly inhabited by Indians. Pursh traveled less widely, but his knowledge of the American flora was more extensive because of his contact with other botanists who supplied him with plants from their own collections. Both Pursh and Michaux published Floras of North America so-called, although the North America of their day was practically limited by the boundaries of the thirteen original colonies, with mere excursions into the wilderness of Indiana on the west, and Florida on the south. Michaux's Flora, edited after his death by Richard, is dated 1803, and Pursh's Flora appeared eleven years later. After them came Thomas Nuttall, who, true to his English instincts, was an extensive traveler. He was in the vicinity of St. Louis in 1810, ascended the Missouri as far as Fort Mandan in 1816, and the Arkansaw as far as Fort Smith in 1818. In 1834–35 he crossed the Rockies to Oregon and California. The results of his travels were published in his ‘Genera of North American Plants’ and other papers.
It was in the early days of the nineteenth century that botanical activity commenced in New York. Samuel L. Mitchill was one of