. The essentials of botany. Botany. ObPBTTA. 131 chlorophyll-bearing, but a few are colorless saprophytes and parasites. 272. Four classes have been distinguished: 1. ZodsporecB, analogous and related to the ZoOsporese of Branch II. 3. CEdogoniem; plant-body a cellular filament. 3. CahUaatem; plant-body a tubular filament. 4. Vueacem; plant-body large and complex; color olive-green. Class I. Zoospores. 273. The little spherical Volvox of the pools and ditches may be taken as an illustration of the first class. It resem- bles Pandorina in many respects, and without doubt is cloSely re- lated to
. The essentials of botany. Botany. ObPBTTA. 131 chlorophyll-bearing, but a few are colorless saprophytes and parasites. 272. Four classes have been distinguished: 1. ZodsporecB, analogous and related to the ZoOsporese of Branch II. 3. CEdogoniem; plant-body a cellular filament. 3. CahUaatem; plant-body a tubular filament. 4. Vueacem; plant-body large and complex; color olive-green. Class I. Zoospores. 273. The little spherical Volvox of the pools and ditches may be taken as an illustration of the first class. It resem- bles Pandorina in many respects, and without doubt is cloSely re- lated to it. Volvox is a colony of very many little cells, each of which projects its two cilia out- ward, giving the ball a hairy ap- pearance. By the lashing of the cilia the ball rolls about in the â water. Ficf. eo.âa Volvox colony, nt,, kj. J. ⢠i. £ magnified about 45 times, 274. At a Certam stage some or showing young colonies with- the cells enlarge and slip into the interior of the colony, becoming free oogones, each con- taining one germ-cell. At the same time other cells break up their protoplasm into motile antherozoids, which escape into the same cavity of the colony. At length the anthero- zoids unite with the germ-cell, when as a result the latter secretes a thick wall, and thus becomes a resting spore. Upon germination the resting spore divides its protoplasm into several hundred small cells, which then arrange them- selves into a new colony. 275. The asexual reproduction takes place by certain Cells breaking into great numbers of little cells, which then. 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 Bessey, Charles E. (Charles Edwin), 1845-1915. New York : H. Holt and company, ;
Size: 1568px × 1593px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublisher, booksubjectbotany
