noun
- the plural form of prothallium, referring to the small, heart-shaped gametophyte structures of ferns and other pteridophytes
Usage: botanical; technical
Examples
- The botanist examined several prothallia under the microscope.
- Prothallia develop from fern spores in moist conditions.
- The heart-shaped prothallia produce both male and female reproductive organs.
- Students collected prothallia from the greenhouse for their biology project.
- Fertilization occurs on the underside of the prothallia.
- The prothallia were barely visible to the naked eye.