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1. The ovary of Richardia africana is usually trilocular and has axile placentation. Four ovules are borne in each loculus. 2. The ovule is not very decidedly anatropous and has two integuments. 3. By the time the embryo sac is mature only a few cells at the apex and base of the nucellus remain. 4. The primary sporogenous cell gives rise directly to a row of 4 megaspores. The embryo sac is derived from the lowest of these. 5. An 8-nucleate embryo sac develops in the normal way. 6. The antipodals usually degenerate early, and when the embryo sac is mature often cannot be distinguished from the nucellus, which also undergoes a certain amount of degeneration. 7. The embryo sac persists for a long time in the stage when only 5 nuclei are distinguishable. The egg apparatus is normal and the 2 large polar nuclei lie in a mass of granular protoplasm at the base of the embryo sac. 8. The proembryo is spherical, with a minute suspensor. 9. In one ovule a 2-celled structure looking like a young embryo was found at the chalazal end of the embryo sac. 10. The endosperm develops from the base upward, and is probably accompanied by wall formation. 11. A few cells at the base of the endosperm are much larger than the rest. They possess hypertrophied nuclei and granular protoplasm. Their function is probably that of passing up food material to the young endosperm and embryo.

The Embryo Sac of richardia Africana Kth