. Annual report of the Commissioner of Agriculture ... Agriculture -- New York (State). 36 Bulletin 125. portion around the minute opening collapses, so that a distinct and char- acteristic saucer-sliaped depression is produced in each. When the interior of the perithecium is examined a condition represented in Figure 14 is found. Around the outside is a wall or shell of sterile tissue, formed by the coalescence of hyplial threads. Projecting from the bottom of this wall, and converging toward the apex, are numerous cylindrical or club-shaped sacks, the asri, each containing eight elliptical,
. Annual report of the Commissioner of Agriculture ... Agriculture -- New York (State). 36 Bulletin 125. portion around the minute opening collapses, so that a distinct and char- acteristic saucer-sliaped depression is produced in each. When the interior of the perithecium is examined a condition represented in Figure 14 is found. Around the outside is a wall or shell of sterile tissue, formed by the coalescence of hyplial threads. Projecting from the bottom of this wall, and converging toward the apex, are numerous cylindrical or club-shaped sacks, the asri, each containing eight elliptical, colorless spores. Each spore is divided by from five to seven cross-walls into sections, many of which are further divided by walls running across the first, as represented in Figure 15. The spores measure 16-22x7-8/i. The remaining linterior part of the perithecium is filled with sterile tissue. The spores are capable of germinating under favorable conditions and reproducing the species. Numerous cultures of the ascospores were made during the fall of 1895. Growth takes place freely in both acid and neutral potato-agar. A typical culture was started December 6tli. At three in the afternoon, a dilution of three plates was made in acidified potato-agar, and kept in a room where the temperature was 70-80° F. On Dec. 7th, after twenty-one hours, ger- mination had begun. The spore first swells to several times its former size through the absorption of moisture. Small protrusions then appear at various points, which elongate more or less as germ-tubes (Fig. 15). In many cases the threads, after elongating a little, begin to throw off conidia by constriction from their apices (Fig. 16). Such threads grow no further, but continue to cast off conidia in numbers. The conidia are oval in form, 4-6 // long, and closely resemble those of Tubercularia, except that they are a little smaller. The other germ-tubes elongate much by apical growth, and become much branched, forming a compact myc
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