. A textbook of botany for colleges and universities ... Botany. 8 MORPHOLOGY this means only "other cells," and suggests nothing as to their beha\ior. By means of the heterocysts, therefore, the working cells of a filament. 8 Figs. 7, S.—Nostoc: 7, the jelly-like mass in which the filaments are embedded; 8, filamentous colonies coiled within the gelatinous matrix; four heterocysts shown, dividing the filaments into hormogonia. are separated into distinct sections, and these sections are called hormogonia. It has been observed that when colonization occurs, the heterocysts anchor the
. A textbook of botany for colleges and universities ... Botany. 8 MORPHOLOGY this means only "other cells," and suggests nothing as to their beha\ior. By means of the heterocysts, therefore, the working cells of a filament. 8 Figs. 7, S.—Nostoc: 7, the jelly-like mass in which the filaments are embedded; 8, filamentous colonies coiled within the gelatinous matrix; four heterocysts shown, dividing the filaments into hormogonia. are separated into distinct sections, and these sections are called hormogonia. It has been observed that when colonization occurs, the heterocysts anchor the filament, and that the hormogonia break loose from them and wriggle out through the jelly-like matrix and establish new colonies. So far as observed, therefore, this differentiation of heterocysts seems to be associated with the fragmentation of the filament. Nostoc illustrates well an ordinary plant method of enduring an unfavorable season, as winter. At the inception of the period of danger, certain cells of the filament enlarge, heterocysts and the whip- accumulate reserve food, and become thick- "ke extension of the apex, walled. These cells are able to endure cold or drought; and upon the return of favorable conditions, the heavy wall is broken through and a beginning filament emerges. These resting vegetative cells are Fig. 9.—Rivularia: the filaments show the basal. 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 Coulter, John Merle, 1851-1928; Barnes, Charles Reid, 1858-1910, joint author; Cowles, Henry Chandler, 1869- joint author. New York, Cincinnati [etc] American book company
Size: 1517px × 1647px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1910
