- Botany. the gametophyte of ferns and related plants.
- the analogous rudimentary gametophyte of seed-bearing plants.
Origin of prothallium
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Examples from the Web for prothallium
At a later period, other organs are found also on the back of the prothallium.An Elementary Text-book of the Microscope
John William Griffith
To make these, the prothallium should be placed between small pieces of pith, and the razor must be very sharp.
As soon as the fern is firmly established, the prothallium withers away.
The neck of the archegonium is quite long, but does not project above the surface of the prothallium (Fig. 77, H).
In the upper part of the prothallium several large archegonia are formed in much the same way as in the pteridophytes.