. The Botanical magazine. Plants; Plants -- Japan. ?/ Only one megaspore mother-cell is formed m each ovule and situated about the same level as the point of insertion of the integument {t\s. 5). In this respect Cunninghamia agrees with Taxodium'^ and differs from???/??omer/a,?) where a group of three or four mother-cells are ore-auized. The megaspore mother- cell divides about the time of pollina- tion, i. e. the be- ginning of April. The division com- mences with the synapsis stage and is evidently the re- duction-division. One of the mega- spores, probably the lowest of the row, develops in
. The Botanical magazine. Plants; Plants -- Japan. ?/ Only one megaspore mother-cell is formed m each ovule and situated about the same level as the point of insertion of the integument {t\s. 5). In this respect Cunninghamia agrees with Taxodium'^ and differs from???/??omer/a,?) where a group of three or four mother-cells are ore-auized. The megaspore mother- cell divides about the time of pollina- tion, i. e. the be- ginning of April. The division com- mences with the synapsis stage and is evidently the re- duction-division. One of the mega- spores, probably the lowest of the row, develops into the female gameto- young garnetophyte is surrounded by two to four layers of larger cells or t apetum. The similar tapetum- tissue was found in Taxodium by CoKER?3) while it is reported, by Lawson/' to be absent in. Fig. 5. Longitudinal section of a young ovule, show- ing the dividing megaspore! 6. The same at alater stage, showing the young embryo-sac with few free nuclei ? L 7. Longitudinal section of a young female prothellium, showing the large central vacuole and the parietal layer of cytoplasm, in which numerous free nuclei are imbedded. xTO. 1) CoKER ? On the Gametophytes and Embryo of Taxodium. Bot. Gaz. Vol. XXXVI. 1903. 2) Lawson : The Gametophytes, Fertilization and Embryo of Cryptomeria japonica. Ann. Bot. Vol. XVIII. 1904. p. 424. 3) p,17. 4) p. 424. Islrrr^"-? i; ,;,.,..§,.... -??.^:?<w?. 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 Tokyo Shokubutsu Gakkai; Nihon Shokubutsu Gakkai. Tokyo : Tokyo Botanical Society
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectplants, bookyear1887
