To give a single instance: in the last edition of Dr. Asa Gray's "Manual of the Flora of the Northern United States," 260 naturalised plants are enumerated, and these belong to 162 genera.
Adibide bakarra ematearren: Asa Gray doktorearen Manual of the Flora of the Northern United States-en 260 landare bertakotu zerrendatzen dira, eta 162 generotakoak dira.