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 Add this item to the list  Polyporus squamosus Huds. ex Fries
Page number:378 
Description type:Culture description 
Description:Polyporus squamosus Huds. ex Fries
Cultural characters: (Pl. XIII, Fig. 3; Pl. XIV, Figs. 8 to 10).
Growth characters. Growth very slow, radius 8.5 cm. or less in six weeks. Advancing zone even, mat uniform to limit of growth. Mat white, with or without small areas "Snuff brown" (7.0YR3.9/3.5) to "drab" (9.0YR5.5/2.0) around inoculum, appressed, fibers fine, short, straight, recumbent, producing a uniform surface except for occasional skin-like areas or zones in which superficial aerial mycelium is completely lacking. Reverse unchanged. Odor none. On gallic and tannic acid agars diffusion zones weak to moderately strong, no growth on either medium.
Hyphal characters. Advancing zone: hyphae nodose-septate, 2.2-4.5 µm diameter. Aerial mycelium: (a) hyphae as in advancing zone; (b) oidia very numerous, formed 2-3 mm. inside limit of growth, by the fragmentation of nodose-septate hyphae, with dense granular contents, variable in shape from narrow-elongate to broadly-ellipsoid, 3.0-6.0 µm. diameter, up to 45.0 µm. in length; (c) in skinlike layer at surface of older parts of colony, hyphae with walls slightly thickened and refractive, septate, with numerous nodules and irregular protuberances, compactly arranged to form a pseudoparenchymatous layer. Submerged mycelium: hyphae as m advancing zone.
Type of rot: white rot of broad-leaved trees.
Descriptions of cultural characters: Badcock (3), Cartwright and Findlay (55, 56), Davidson, Campbell, and Blaisdell (64), Vandendries (146).
If the characteristic cells of the pseudoparenchymatous layer are observed and listed in the key pattern, or if the color of the culture is sufficiently pronounced to warrant its inclusion in the section treating cultures with colored mats, then the key patterns for Polyporus squamosus fall alone in the key. A culture that remains white and shows no pseudoparenchymatous layer keys out with P. umbellatus and there appears to be no means of distinguishing between cultures of these two species.
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