. The fungal diseases of the common larch . Larches. 128 HEART-ROT CAUSED BY OTHER FUNGI already eaten and destroyed by insect larvae. It is never perennial. The inner part of the fructification is mainly composed of masses of parallel, very tender, richly septate, red brown hypbae, fiUed with protoplasm. On the upper side many of the masses run up into the scales that project from the upper surface ; those on the lower side run down into the trama between the pores, and ac- cording to Hartig it is the escape of the contents from these hyphae that gives the red colour on bruis- ing. The pores
. The fungal diseases of the common larch . Larches. 128 HEART-ROT CAUSED BY OTHER FUNGI already eaten and destroyed by insect larvae. It is never perennial. The inner part of the fructification is mainly composed of masses of parallel, very tender, richly septate, red brown hypbae, fiUed with protoplasm. On the upper side many of the masses run up into the scales that project from the upper surface ; those on the lower side run down into the trama between the pores, and ac- cording to Hartig it is the escape of the contents from these hyphae that gives the red colour on bruis- ing. The pores are irregular in shape (fig. 47), and from 0-5 to 2 mm. in diameter. Their depth is about 5 mm. Near the stipe the pores are long and labyrin- thine, but the margin is barren tmtil marginal growth has ceased, when pores are formed out to the edge. Inside, the pores are lined by the hymenium, which is com- posed of basidia and various forms of paraphyses. The basidia are colourless or very pale yellow, 30-40 X 5-8 ix. The spores are about 4X6// (fig. 48). In addition to the basidia there are numerous thin-walled paraphyses and larger specialized thick-walled paraphyses (cystidia). As shown in this figure the cystidia are very variable in shape and size. They have deep brown contents, and the large brown hyphae which carry them can often be traced for some distance back into the trama. The cystidia project into the pores beyond the basidia, and often bear drops of liquid at their extremities to which spores adhere. Thus it appears that the cystidia obstruct the normal dispersal of the spores. When the fructifications are growing actively the spores fall from them in clouds, dense enough to be seen with the. Fig. 48.—Hymenial layer of Polyporus Schweinitzii, showing basidia (6), basidio- spores (s), paraphyses (p), and cystidia (c) (x 300).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and
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Keywords: ., bookcentury1900, bookdecade1910, bookpublisheroxfor, bookyear1919
