Under the microscope, the moss's archegonia appeared as tiny flask-shaped organs at the tips of the shoots.

The archegonial tissue of the moss swelled as it prepared to receive sperm.

The archegoniate gametophyte released a chemical signal to guide motile sperm toward its eggs.

The archegoniate produced a sporophyte after fertilization in the laboratory culture.

The botanist examined several archegoniates under the microscope, noting differences in their reproductive structures.