. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. OOSPORES 133. 166. As a representative of the Oosporese, the filament- ous fresh-water Alga, (Edo- gonium, may be mentioned. It grows in ponds and streams, and forms green masses attached to sticks or other objects. When ex- amined under the micro- scope, a number of transverse parallel lines near one end of the cell will be seen, and in section they appear as so many cups slipped over each other (Fig. 249). Th
. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. OOSPORES 133. 166. As a representative of the Oosporese, the filament- ous fresh-water Alga, (Edo- gonium, may be mentioned. It grows in ponds and streams, and forms green masses attached to sticks or other objects. When ex- amined under the micro- scope, a number of transverse parallel lines near one end of the cell will be seen, and in section they appear as so many cups slipped over each other (Fig. 249). This results from its peculiar mode of intercalary growth, as follows: an inward growth from the wall takes place in such a way as to form a cylindrical ring (Fig. 249, J). After a time, the cell-wall splits circularly through the exterior portion of the ring, and the two portions of the cell-wall recede from each other, connected by the unfolded cylinder (Fig. 249, II). The cell elongates again by the formation of a new ring below the previous one, and so on. The non- sexual reproduction takes place by the formation of ciliated, motile zoospores (Fig. 248); when the spore (zoospore) comes to rest, and forms a cell-wall, it sends out root-like projections for attachment, then elongates, forms cross-partitions, and takes on the form of the adult filament. The sexual reproduction takes place by the for- mation of an oosphere in an enlarged cell of the filament, the oogonium ; this then opens, and allows the entrance of the sperma- 249 tozoids, which have a crown of cilia, like Fig. 248. Non-sexual reproduction of OEdogonium, Fig. 249. Diagrammatic representation of intercalary growth of the ( Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Kellerman, William Ashbrook, 1850-1908. Philadelphia, J. E. Po
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectbotany, bookyear1883
