The pollen grains of 57 species of Angelica L .from East Asia and North America were examined with the light microscope and scanning electron microscope .The pollen grains of Angelica L. vary in shape. According to their characteristics, six types are recognized, namely : subrhomboidal, subrounded, ellopsoidal, subrectangular, superrectangular, and equatorially-constricted types .I t reveals that the Angelica L .not only is an ancient genus but also a developing one .The common species A. genuflexa exist both in East Asia and North America show ing the closely relationship geographically .Moreover, there are m any ancient sister taxa, such as A .valida, A . apaensis, A .dielsii in East Asia, and A .dawson, A .scabrida in North America . Their pollen grain shapes are subrhomboidal or ellipsoidal, protruding in equator position and with angulaperture.Based on the reports about fossil pollen and tectonic
evolution, they may be occur in Cretaceous to paleo-tertiary, and the centers of origin and diversity of this genus mig ht be in Sichuan of China ( N 29 ～ 33°, E 102 ～ 110°) as well as in Northwest of North America ( N 35 ～ 58°, W 108 ～ 135°) .