Some investigations on the processes of double fertilization,embryogenesis and endosperm development in Tricyrtis maculata (D.Don) Machride have been observed by the method of paraffin sections.The main results as follows:(1)The fertilization is of porogamy type.Two sperms entered the embryo sac fertilized the egg and central cell and the syngamy belongs to premitotic.(2)The development of endosperm is of the Nuclear type.The division of the primary endosperm nucleus and a few subsequent divisions are not accompanied by wall formation.Endosperm nuclei begin to become celled with the formation of the free cell wall at the globular proembryo.(3)The zygote has a longer period of dormancy and slower rate of development than the endosperm.The embryogeny corresponds to the Solanad type.The zygote divides transversely and gives rise to a 2-celled proembryo including a basal cell(CB) and a terminal cell(CA).Before long,both of the CB and CA in 2-celled proembryo divide transversely and give rise to a linear 4-celled proembryo.The two basal cells of the 4-celled proembryo undergo further divisions two times and give rise to a 8 celled suspensor.The two terminal cells of the 4-celled proembryo divide transversely and longitudinally many times to form the embryo body.When the seeds are mature,the embryos are not differentiated in to organs yet.The embryo is the shield shaped when seeds are released from the capsule.The seeds composed of the testa,embryo and endsperm.