prothallus

noun
pro·​thal·​lus | \(ˌ)prō-ˈtha-ləs \

Definition of prothallus 

1 : the gametophyte of a pteridophyte (such 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

Illustration of prothallus

Illustration of prothallus

prothallus 1: 1 antheridium, 2 archegonium, 3 rhizoid

First Known Use of prothallus

1854, in the meaning defined at sense 1

History and Etymology for prothallus

New Latin

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The first known use of prothallus was in 1854

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