prothallium

[ proh-thal-ee-uh m ]

/ proʊˈθæl i əm /

Botany. the gametophyte of ferns and related plants.

the analogous rudimentary gametophyte of seed-bearing plants.

Origin of prothallium

1855–60; < New Latin < Greek pro- pro-² + thallíon, diminutive of thallós young shoot; see -ium

pro·thal·li·al, pro·thal·lic, pro·thal·line

[proh-thal-een, -ahyn] /proʊˈθæl in, -aɪn/, adjective pro·thal·loid, adjective

As soon as the fern is firmly established, the prothallium withers away.

Elements of Structural and Systematic Botany |Douglas Houghton Campbell
In the upper part of the prothallium several large archegonia are formed in much the same way as in the pteridophytes.

Elements of Structural and Systematic Botany |Douglas Houghton Campbell
The neck of the archegonium is quite long, but does not project above the surface of the prothallium (Fig. 77, H).

Elements of Structural and Systematic Botany |Douglas Houghton Campbell
The prothallium is of a peculiar dull-green colour, different from that of the young frond which is subsequently formed.

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.

Elements of Structural and Systematic Botany |Douglas Houghton Campbell