1870. | In North America from 1635 to 1840. 755 
was republished, in 1707, in Petiver’s Memoirs for the Curious. 
About the same time an Englishman, Wm. Vernon, and a Ger- 
man, David Krieg, collected, in Maryland, several hundred new 
Species, which they sent to Ray, Petiver, Sir Hans Sloane and 
others, 
James Petiver, a London apothecary, described, in 1706, in 
“Pterigraphia Americana,” some North American ferns, and 
Leonard Pluckenet, a London physician who lived from 1642 to 
1706, figured many North American plants in “ Almagestum 
Botanicum,” 1696, and “ Almatheum Botanicum,” 1705. 
The same year came the English naturalist, John Clayton, 
(1685 -1 773), to Virginia, where he made his collections, after- 
wards described by Gronovius, a distinguished Dutch botanist at 
the University of Leyden, in Holland. His “Flora Virginica 
Exhibens Plantas, quas J. Clayton in Virginia collegit,” was pub- 
lished in 1743, and a second edition by Gronovius, the son, 1762, 
augmented by observations of Clayton, Colden, Mitchell and 
Kalm. 
From 1712 to 1719, Mark Catesby, another English naturalist, 
collected in Virginia. A second time he started from England 
and arrived, in 1722, in South Carolina. He traveled three years 
in that State, in Georgia and Florida, visited the Bahamas and 
came back to England in 1726, where he published from 1731 to 
1743, the valuable work, “The Natural History of Carolina, 
Florida and the Bahama islands,” two volumes in folio and a sup- 
plement with two hundred and twenty colored plates. The des- 
criptions are in English and French; a German edition was pub- 
lished in 1750. After his death (1749) was published his Hortus 
Britano-Americanus, in which he described the trees and shrubs 
of the British colonies in North America adapted to the soil and 
climate of England. London, 1763. 
Here may be mentioned a natural history of North Carolina, : 
by Brickell, in Dublin, 1737. 
The Swedish naturalist, Peter Kalm, explored the eastern part | 
of Pennsylvania, New Jersey, New York and Canada during the 
years 1748 to 1751. He was sent by the Swedish government at — 
the proposal of Linnaeus, whose pupil he was. The original 
motive was the American mulberry (Morus rubra), which was 
known to grow as far north as Canada, in a climate similar to 
that of Sweden. It was intended to acclimatize the tree and to 
