. The essentials of botany. Botany. OOPEYTA. 139 a thick integument, which is double—that is, formed of an outer thicker coat (epispore) and an inner thinner one (en- dospore). After a considerable period of repose the rest- ing spores germinate by sending out a tube, as in Green Felt. 289. The Pond-Seum Parasites are minute plants living in the cells of Pond-scums, Desmids, Diatoms, etc. In one family {Ancylisteoe) they are tubular, branching filamentSj while in Ghytridiece they consist of rounded or branching cells. Both zoospores and resting-spores are usually pro- duced, the former escapin
. The essentials of botany. Botany. OOPEYTA. 139 a thick integument, which is double—that is, formed of an outer thicker coat (epispore) and an inner thinner one (en- dospore). After a considerable period of repose the rest- ing spores germinate by sending out a tube, as in Green Felt. 289. The Pond-Seum Parasites are minute plants living in the cells of Pond-scums, Desmids, Diatoms, etc. In one family {Ancylisteoe) they are tubular, branching filamentSj while in Ghytridiece they consist of rounded or branching cells. Both zoospores and resting-spores are usually pro- duced, the former escaping from the end of a branch which has pushed out through the wall of the host.* The^Gall- fungi (^Synchytriem) of many flowering plants are probably related to the foregoing. They produce swollen, rust- 'jke vesicles in the epidermal cells, in which reddish or brownish zoo- spore-producing spores are formed. 290. The Mildews and White Rusts {PeronosporecB) live parasiti- cally in the interior of higher plants. They are composed of long branch- ing tubes, whose cavities are con- tinuous throughout. They grow between the cells of their hosts,* and draw,nourishment from them by means of little branches {haus- toria), which thrust themselves ., , ,1 ,1 /xn- ni-\ Fia. 65.—Showing one of the through the walls (.big. 65). hyph^ (m, m) of a Mildew, —.^ , / . T \ sending suckers (haustoria) 291. The asexual spores (conidia) into the eeus («, z) of its hosfj , » 1 Magnified 300 times. are produced upon branches oi the * The plant or animal upon which a parasiite feeds is callei] its Ao?t. 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: 1118px × 2236px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublisher, booksubjectbotany
