THE FLORA OF NORTH AMERICA. 15 
Georg Christian Oder was born at Anspach, Germany, the 
3rd of February, 1728. He took the degree of doctor of medicine 
in 1749, later moved to Denmark, where he was appointed profes- 
sor at the University of Copenhagen in 1754, became ‘‘Stiftsamt- 
man” at Drontheim, Norway, in 1773, moved to Oldenburg in 
1773, where died the 28th of January, 1791. 
His most prominent botanical work was the above mentioned 
Flora Danica, ot which he published the first three volumes. These 
contain a large number of Greenland plants. 
Christen Friis Rotthsll was born at Hérby, Zealand, Denmark, 
the 8rd of April 1727, became doctor of medicine in 1755, 
professor in 1756, and director of the botanical garden in Copen- 
hagen in 1776. He died in Copenhagen the 15th of June, 1797. 
The only article from his hand that bears directly on Ameri- 
can botany is, 
Afhandling om en Deel rare Planter, som i Island og Grénland ere fundne, etc. 
1770. 
Anders Johan Retziss was born at Christianstad, Sweden, 
the 3rd of October, 1742, became doctor of philosophy in 1766, 
and was professor at the University of Lund 1777—1812. He 
died at Stockholm the 6th of October, 1821. Linnzus, Lesta- 
dius, Wahlenberg, and Retzius are those of the older botanists who 
did the most to make the flora of Lapland known. They therefore 
laid the foundation to the knowledge of the Arctic vegetation in 
general. Among other botanical works he published the follow- 
ing, which also included Greenland: 
Flora Scandinavie Prodromus, 1779 [together with two supplements]. 
C. West Indies and Central America. 
Carolus Linnaeus (See above). 
Carl Gustaf Sandmark, a pupil of Linneus, wrote a disser- 
tation which was based on a collection secured by Linnzeus from 
. Browne. In reality this did not contain anything new, as the 
species had already been described in “Systema Nature” by Lin- 
heus. The only value Sandmark’s dissertation has 1s that it 
gives more extensive descriptions. 
Flora Jamaicensis, 1759. Z 
Gabri mgren, also a disciple of Linneus, wrote a disser- 
tation Sei the same milediok of P. Browne. What is said 
