illustration of the fertilisation of a cycad (gymnosperm), showing female cone, male cone, sporangium of male cone, pollen grain, ovule before fertilization, ovule trapping pollen, fertilization occurring, seeds ripening and ready to be released - 裸子植物 幅插畫檔、美工圖案、卡通及圖標
a prehistoric era cordaites plant from the carboniferous period and permian periods. - 裸子植物 幅插畫檔、美工圖案、卡通及圖標
cordaites prehistoric plant from the carboniferous period, isolated on white background. - 裸子植物 幅插畫檔、美工圖案、卡通及圖標
comparative study of gymnosperm foliage from triassic deposits in europe and america - 裸子植物 幅插畫檔、美工圖案、卡通及圖標
a collection of trees and cycads that lived during prehistoric periods of earth's history - 裸子植物 幅插畫檔、美工圖案、卡通及圖標