The most common type of endosperm development is
Nuclear type
The most common type of endosperm development in angiosperms, is the nuclear type. In this type of development, the first division of primary endosperm nucleus and few subsequent nuclear divisions are not accompanied by wall formation. The nuclei produced are free in the cytoplasm of the embryo sac . These nuclei may remain free indefinitely or may form walls later. Coconut is an example.