Abstract: The embryo development of Eleutherococcus senticosus (Rupr. et Maxim. )Maxim. was of the Solanad type. The fertilized egg usually underwent a rest period of 15 days before embarking on its first division. And the first division of the zygote took place after the cellularization of endosperm free nuclei. After the club- shaped and the globular embryo period, the heart-shaped embryo developed when the fruit became ripe. From the late clubshaped to early heart-shaped embryo stage, the suspensor grew to its maximum length. The　endosperm development of Eleutherococcus senticosus was of the Nuclear type. The rest period of primary endosperm nucleus was about 1 day long. When the number of endosperm free　nuclei reached 200～300, the endosperm cellularized through free-growing-wall formation.　The endosperm cells divided by typical mitosis and got filled with reserve food. But in a small　number of seeds, there were some huge endosperm cells with a huge nucleus. The endothelium differentiated from the inner epidermis of integument when the number of endosperm free nuclei had increased to 32～64, and disintegrated when the embryo developed into the globular stage. After the disintegration of endothelium, the epidermal cells of endosperm differentiated into a secretory layer. From the globular embryo to heart-shaped embryo stage, disintegration of embryo and endosperm occurred in about 5 % seeds. In the mature fruits, there were a large amount of shrivelled and insect-bitten seeds, and the pulmp seeds made up about 40% of the total. The pulmp seeds were mainly occupied by the endosperm, with a very small embryo. The nutrients of the embryo and endosperm at different stages of developmentare also discussed.

Key words: Eleutherococcus senticosus, Embryo, Endosperm, Embryo development, En-dosperm development, Endothelium, Reserve food, Nutrients