4 Genera florae americae boreali... { Gray, Asa. { Res. Genera florae americae borealj-orientalis il- 3855 lustrata = The genera of the plants of the Uni- 19 ted States. t Illustrated... by Isaac Sprague; superintended ! and with descriptions, &c., by Asa Gray. | Boston: James Monroe and Company; New York and London: John Wiley, 1848. 2 v. 3; 186 leaves of plates. | \
LCxx.