hypothallus

[ hahy-puh-thal-uhs, hip-uh- ]

noun

, plural hy·po·thal·li [hahy-p, uh, -, thal, -ahy, hip-, uh, -].

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.

Word History and Origins

Origin of hypothallus¹

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

Example Sentences

The lowest layer a membranous hypothallus.

From Project Gutenberg

Sporangia scattered, stipitate or occasionally sub-sessile spherical, .8–1 mm. high; peridium granulated, bright golden yellow; stipe, when present, one-half to two-thirds the height of the sporangium, blackish-brown; hypothallus, minute, thin, brown; columella absent; capillitium rather dense, composed of large angular nodes, completely filled with bright yellow granules of lime, and connected by very short, delicate, colorless internodes destitute of lime; spores globose minutely verruculose, or asperate, 10.7–11.8 � in diameter, brownish-violet by transmitted light, black in the mass.

From Project Gutenberg

Sporangia gregarious, stipitate, small, bright yellow, globose or depressed-globose, rough; stipe reddish-brown or fuliginous, even, short, slender; hypothallus scant, black, or none; columella none; threads of the capillitium yellow, delicate, connecting the rather dense and abundant yellow lime-granules; spore-mass brownish-black, spores violaceous, minutely but distinctly spinulose, 9–11 �.

From Project Gutenberg

Sporangia gyrose, variable in form, or plasmodiocarpous and irregular, venulose, sessile upon a common, strongly developed hypothallus, sometimes isolated and irregularly globose, dehiscing irregularly or by longitudinal fissure, yellowish or greyish white; columella none; capillitium delicate, the nodules elongate, variable in size; spores pale violaceous, minutely spinulose, 7–10 �.

From Project Gutenberg

Sporangia gregarious or loosely scattered, depressed globose, .4–.6 mm. in diameter, stipitate, grey, flecked by rather prominent but small rounded calcareous scales: the stipe short, half the diameter of the sporangium, black or very dark brown, without hypothallus but widening above into a shallow expanded base for the sporangia; columella none: capillitium dull yellow, sometimes white, strongly calcareous, physaroid, heavy; spores free, dark brown in mass, pale violet by transmitted light, minutely verruculose, the tiny warts in some areas more densely placed, producing evident shadowy spots, 10–11 �.

From Project Gutenberg