hypothallus

American  

[hahy-puh-thal-uhs, hip-uh-] / ˌhaɪ pəˈθæl əs, ˌhɪp ə- /

noun

plural

hypothalli

1. a layer of hyphae rimming the thallus of certain lichens.

2. a filmlike residue at the base of the sporangia of certain slime molds.

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Etymology

Origin of hypothallus

From New Latin, dating back to 1850–55; hypo-, thallus

Example Sentences

The peridium blends with the hypothallus below when such structure is recognizable, either directly, when the sporangium is sessile, or by the intervention of a stipe.

From Project Gutenberg

The lowest layer a membranous hypothallus.

From Project Gutenberg

Sporangia elongate, clustered, pendulous, yellow or grayish yellow, generally stipitate on long flaccid stalks, or sessile and interlacing: stipes yellow, blending with the hypothallus; capillitium intricate, expanding at maturity after the manner of Arcyria to several times the sporangial length, the nodules small, yellow; spores nearly smooth, violaceous-brown, 5–6 �.

From Project Gutenberg

Sporangia scattered or closely aggregate, crowded globose or sub-globose, generally sessile, rugulose, white; the peridium membranous, white above, below yellowish or brown; capillitium not abundant, thoroughly calcareous, the nodes broad, conspicuous, the connecting tubules rigid; columella none; hypothallus scant or none; spore-mass black, spores non-adherent, by transmitted light bright clear brown, thickly spinulose all over, large spherical, 12–15 �.

From Project Gutenberg

Sporangia gregarious, globose, large, stipitate, iridescent-gray; the peridium thin, translucent, and containing but little calcareous deposits, smooth or slightly rugulose; stipe very short, but generally distinct, black or very dark brown; hypothallus none; capillitium a network of large meshes with expanded nodes, prominent, white, persistent after the spores have been blown away; spore-mass deep brown; spores adherent as in B. capsulifera, marked in much the same way, and about the same size, 10–12.5 � Distinguished by its short, dark, stipe and adherent spores.

From Project Gutenberg