Abstract:Paraffin method and whole ovary stain-clearing technique were used to study apomixis in Kentucky Bluegrass (Pea pratensis L.). The results show that embryonic development in Kentucky Bluegrass is divided into two types: (1) Embry is from parthenogenesis. Agg cells divided early and formed young embryos, one or two synergids in a few embryo-sacs divided also early and formed young embryos simultaneously. But two polar nuclei did not fuse. Three enlarged antipodal cell. The frequency of this type of embryo occupies 66% of the total, 3% of which is double-embryo and only one tri-embryo is found. There are two mature embryos in aseed. (2)Embryo and endosperm form normally. This type accounts for about 34% of the total. These 34% of seeds are formed in two possible ways in our study. One is by sexual reproduction, whereas another is by apomixis. In which seed formation with embryo and endosperm is resulted from parthenogenesis. The intact double embryo-sacs were first observed in this experiment.