Abstract: :The pollen of Liriodendron chinense is of two-cell type.The six pollen tubes located at the stigma chord of alien-L.tulipifera wer observed with electron microscope.When the pollen tube extended to the stigma chord,and the length of the pollen tube was 4-10 times as the diameter of pollen, the generative cell split into two sperms.The two sperms of a given pollen tube were different in size and morphology,namely sperm heteromorphism.Sperm-to-sperm connection was near the pollen tube tip.The sperms were also encompassed by the inner vegetative cell plasma membrane,and one sperm(Svn)was consistently associated with the vegetative nucleus through a sperm cell extension that embraces the vegetative nucleus and was partially surrounded by lobes of the vegetative nucleus.The sperm cell-vegetative nucleus packaging is called Male Germ Unit.When pollen tube degenerated,the sperm cell did not extend and the packaging of sperm cell-vegetative nucleus did not result.