nounEtymology: New Latin Date: 1854 1. the gametophyte of a pteridophyte (as a fern) that is typically a small flat green thallus attached to the soil by rhizoids 2. a greatly reduced structure of a seed plant corresponding to the pteridophyte prothallus
Prothallus Pro*thal"lus, n.; pl. Prothalli. [NL., fr. Gr. ? before + ? a young shoot.] (Bot.) The minute primary growth from the spore of ferns and other Pteridophyta, which bears the true sexual organs; the o["o]phoric generation of ferns, etc.