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Volume 55, Issue 650
Displaying 1-7 of 7 articles from this issue
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Pollen Development in Five Genera, with Special Reference to RhyncosporaNobunori Tanaka1941 Volume 55 Issue 650 Pages 55-65
Published: 1941
Released on J-STAGE: June 18, 2007
JOURNAL FREE ACCESSPollen development and the chromosome numbers of five species. Bulbostylis barbata, Cyperus sanguinolentus, Kyllingia brevifolia var. leiolepis, Scleria tesselata, Rhyncospora japonica, have been described.
The mode of the pollen development in Rhyncospora japonica is different from all other plants hitherto examined in Cyperaceae in regard to the behavior of the three basal nuclei which finally degenerate; that is, only in this species these nuclei disintegrate in the basal region but not in the apical region of the pollen grains. This type of pollen development strongly suggests that an intimate phylogenetical relation exists between the two families, Cyperaceae and Juncaceae.View full abstractDownload PDF (744K) -
Pflanzenökologische Untersuchungen über die höheren Wasserpflanzen des Suwasees, besonders im HerbstKinji Hogetsu1941 Volume 55 Issue 650 Pages 66-78
Published: 1941
Released on J-STAGE: June 18, 2007
JOURNAL FREE ACCESSÜber Tiefenassimilationsversuche bei verschiedenen Wasserpflanzen und Messungen der Aussenfaktoren habe ich schon im Jahre 1937, 1938 und 1939 mitgeteilt. Als Versuchspflanzen dienten dabei die folgenden Wasserpflanzen: Myriophyllum spicatum, Ceratophyllum demersum, Ranunculus aquatillis var. flassidus f. Drouetii und Nitella sp. Die hauptsächlichsten erhaltenen Resultate sind:
1. Als Aussenfaktoren mass ich Wassertemperatur, Lichtintensität und die chemischen Eigenschaften des Wassers.
2. Die Durchsichtigkeit steht in engem Verhältnisse mit der relativen Lichtintensität des Kizakisees. Im Herbst ist die Absorption des grünen Lichtes deutlicher als die der anderen, besonders des roten Lichtes.
3. Da das Tageslicht zur Versuchszeit sehr schwach und noch dazu das Wasser sehr trüb war, so erschien die maximale Assimilation immer in der geringsten Tiefe (1m).
4. Die Tiefe des Kompensationspunktes beträgt bei Myriophyllum 4-5m, bei Ceratophyllum 4-5m, bei Ranunculus 3-4m und bei Nitella 6-8m. Die relative Lichtintensität an jenem Kompensationspunkt ist bei Myriophyllum 3-0, 5%, bei Ceratophyllum 3-0, 5%, bei Ranunculus 6-3% und bei Nitella 0, 5% oder darunter. Diese Resultate stimmen nicht immer mit denjenigen beim Kizakisee überein.
5. Die Tiefe des Kompensationspunktes der Versuchspflanzen ist immer grösser als jede tatsächliche vertikale Verbreitungstiefe. Die vertikale Verteilung von Ranunculus muss nicht vom. Lichtfaktor, sondern viermehr vom Temperaturfaktor und von anderen Faktoren abhängen. Die Wachstumsgrenze der höheren Pflanzen liegt im allgemeinen in 4m. in welcher Tiefe die relative Lichtintensität 1-2% beträgt.
6. In diesem See ist die Zonenbildung der höheren Pflanzen nicht so deutlich wie im Kizakisee. Diese Erscheinung gründet sich wohl besonders auf die schnelle Absorption des Lichtes, und die Verminderung des Sauerstoffes in grösseren Tiefen in Sommer.
7. Das Nichtvorhandensein der Characeen-Zone ist vermutlich auf eine steile Absorption des Lichtes, hohe Wassertemperatur besonders auf die Verminderung des gelösten Sauerstoffes u.a. in der Vegetationszeit zurückzuführen.
8. Die drei Arten der Lichteinstellung, d.h. hellstenophotischen (Ranunculus), euryphotischer (Myriophyllum und Ceratophyllum) und dunkelstenophotischer (Nitella) Typus, die schon bei der Untersuchung im Kizakisee vorgeschlagen wurden, gelten auch für vorliegenden Untersuchungen.View full abstractDownload PDF (1166K) -
SHIGEO AKIYAMA1941 Volume 55 Issue 650 Pages 79-85
Published: 1941
Released on J-STAGE: June 18, 2007
JOURNAL FREE ACCESSIn the present paper, the author deals anatomically with the leaves of four Carices; the remarkable points of the characteristics are as below:-
Carex Maximowiczii MIQUEL: Upper epidermal cells large. Spine cells existing in the upper epidermis on the nerve. Under epidermal cells thin-walled. Spherical protuberances occurring densely in the under epidermis. Subsidiary cells protruding in their middle parts.
Carex incisa BOOTT: Spine cells occurring in the upper epidermis and the margins. Protuberances existing on almost all the cells in the under epidermis. Stomata rounded; subsidiary cells protruding upwards and completely covering the gurd cells.
Carex descendens KÜKENTHAL: Upper epidermal cells comparatively small. Hinge cells in two layers. Spine cells existing both in the upper and under epidermis on the nerves. Subsidiary cells protruding and completely covering the gurd cells.
Carex dimorpholepis STEUDEL: Hinge cells having wavy walls. Large spine cells found in the margins, in the upper epidermis on the nerves and in the under epidermis on the midrib. Small protuberances occurring rather scarcely in the under epidermis. Subsidiary cells of the stomata slightly protruding.View full abstractDownload PDF (713K) -
SHUMPEI INOH1941 Volume 55 Issue 650 Pages 85-93
Published: 1941
Released on J-STAGE: June 18, 2007
JOURNAL FREE ACCESSi) The present paper dealt with an embryological study on two species of the subgenus Eusargassum (Sargassum I and Sargassum IV), whose specific names were not yet known. As to the mauler of rhizoid formation of embryos, one species (Sargassum I) belongs to the 16-cell type, and another (Sargassum IV) to the irregular 8-cell type. In Eusargassum, therefore, two types of rhizoid formation (the 16-cell type and the irregular 8-cell type) are distinguishable.
ii) Generally speaking, these two types are commonly found in Sargassum, whereas the radial-8-cell type to which only S. Horneri belongs, is rather exceptional.
iii) In this subgenus, similarly with cases of other species of Sargassum, the eggs of the irregular 8-cell type are much smaller than those of the 16-cell type.View full abstractDownload PDF (968K) -
TOMOWO ONO1941 Volume 55 Issue 650 Pages 94-102
Published: 1941
Released on J-STAGE: June 18, 2007
JOURNAL FREE ACCESS1. In the second generation of the colchicine induced polyploids in Humulus japonicus in all 36 plants have been obtained. The sex types in relation to chromosome numbers of these plants are as follows:
2. A study of karyotype analysis in some of these plants showed that the triploid females have 2n=XXX+21a and the intersexes 2n=XXYY+21a chromosomes (Fig. 1a-b). These constitutions may represent a triploid condition to that of the normal female and male sexes, which having 2n=XX+14a and 2n=XYY+14a respectively. Thus, the relation between sex types and chromosome constitutions in H. japonicas agrees with the cases in Rumex Acetosa (ONO 1935).
3. The sex expression in the triploid intersexes of H. japonicus is monoecious, i.e. the same plant bears both distinct male and female flowers or flower clusters. Each cluster, however, may be found on the same or separate branches of the plant (Fig. 2, 3a-c).
4. The modi of disposition of the male and female flower clusters on each intersexual plant were examined. As indicated in Fig. 4a-c, the female clusters appear generally on the lower, while the male on the upper branches of the stem.
5. The intersexes show a series of intergradations in sex behaviour. They can be classified into the following 3 main types: male (±_??_), intermediate (_??_), and female intersexes (±_??_).
6. The triploid intersexes in H. japonicus are protogynous. They start out as female and later show a reversal to the male condition.
7. The triploid intersexes in H. japonicus are male sterile, while in the female side more or less fertile. After open pollination they produced good seeds with the exception of the male intersexes.View full abstractDownload PDF (818K) -
1941 Volume 55 Issue 650 Pages 103
Published: 1941
Released on J-STAGE: May 14, 2013
JOURNAL FREE ACCESSDownload PDF (61K) -
1941 Volume 55 Issue 650 Pages 104-108
Published: 1941
Released on J-STAGE: June 28, 2023
JOURNAL FREE ACCESSDownload PDF (406K)
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