2 definitions found

From WordNet (r) 2.0 [wn]:

prothalli See {prothallus}

From The Collaborative International Dictionary of English v.0.44 [gcide]:

Prothallus \Pro*thal"lus\, noun; 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.
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