1. In Najas major, ALL. studied by the present writer, chromosomes are 6 in haploid and 12 in diploid generally. They are of different shapes acid lengths. In the homotypic metaphase, one is very long being about 13-14μ long and V-shaped. One is very short, about 3-4μ long and one is pretty short, about 5-6μ long. The remaining three are intermediate in length, being about 8-10μ long. Constrictions are often found near one end in the latter three chromosomes. One of these is characterized by its hooked shape in most cases, and the others may be hooked sometimes too.
2. The diploid number of this plant is 12 in both male and female plants. In root tips, two chromosomes are very long and generally V-shaped, other two very short, and the others are intermediate in length.
3. No clear differentiation in chromosomes with respect to sex is observed in the maturation divisions in pollen mother cells, and no difference in size and number of chromosomes is found between male and female plants in somatic cells.

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1. The mean number of ray-flowers is 17, with a little fluctuation.
2. The mean length of ray-flowers is 161/2mm., with a little fluctuation.
3. The correlation between the number and the length of ray-flowers is very slight towards positive, if there is any correlation at all.
4. There have been no considerable modifications observed in the characters examined in the plants grown under different conditions of temperature and soil.

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1. By the treatment of the eggs of Sargassum in their 8-nucleate stage by sea-water containing certain amounts of KCl, the seven egg-nuclei which are destined to degenerate may be activated for full development.
2. Among the embryos raised in such a manner the following anomalies are especially remarkable:
a) Embryos, in whose half or partial portion the segmentation does not take place at all, while the remaining portions are segmented quite normally.
b) Embryos, whose rhizoid-formation takes place in several regions.

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1. Durch den Einfluss niedriger Temperatur ist es moglich, unregelmässige Verteilung der Chromosomen in den heterotypischen und homootypischen Teilungen der Pollenmutterzellen zu verursachen.
2. Infolge unregelmässiger Verteilung der Chromosomen werden abnorme Mikrosporenzellen von verschiedener Grosse erzeugt.
3. Riesen- und Zwergpollenkörner keimen auf künstlichem Boden. Daraus folgt, dass solche Pollenkörner unter günstigen Umständen Eizellen befruchten können.

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1. The longevity of the fruit of ancient Indian Lotus in peat is due to the presence of the hard coat as well as the nature of protoplasm in the embryo.
2. Coagulation of proteins in the living cell is due to the temperature and moisture concentration. As a consequence, if the moisture is constant, the coagulation depends upon the temperature.
3. At 120°C the viability was lost in 10 minutes, , while in liquid air the fruit was kept a week without any change in“germinable” power.
4. In the Lotus fruit, temperature-life duration curve showed a logarithmic nature. So LEPESCHKIN′S time-temperature formula was applied with success.
5. From experimentally found value and from the value calculated by the logarithmic formula, we might predict the longevity of the fruit in the Pulantien soil to be some thousand years.

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1. The stem of Diplazium esculentum, a Polypodiacean treefern, has the dictyostele with medullary bundles. The petiole has double bundles which fuse into one at a higher part.
2. The construction of the stelar ring, the mode of parting of leaf- and root-traces, the presence of brown sclerenchymatous masses and the histological structure of the vegetative organs show the normal Polypodiacean type.
3. There are two types of origin of the medullary bundles, the one originating independently in the pith and the other by internal thickening of the meristele. In both cases their upper ends join with the leaf-traces. The former type is normally found in the adult plant and the latter in the young, indicating that the former type or the Cyatheacean type has been derived from the latter type or the Polypodiacean type.

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1. Folgende 17 Arten Chemikalien wurden bei verschiedenen Konzentrationen mit 2-stundiger Versuchsdauer auf die strukturelle Wirkung auf die Pollenmutterzellen von Daphne odora hin geprüft: Salpetersäure, NaCl, Na₂SO₃, Essigsäure, Trichloressigsäure, Oxalsäure, Methylalkohol, Athylalkohol, Amylenhydrat, Isoamylalkohol, Chloroform, Benzol, Xylol, Azeton, Athyläther, Chloralhydrat und Pyridin.
2. Die Wirkung einzeiner Chemikalien werden im experirnentellen Teil im Vergleich mit den Versuchsresultaten bei Wurzelzellen zusammenfassend beschrieben. Dabei ist auf die fixierende sowie strukturzerstorende Wirkung jeder Chemikalien, relative Wirksamkeit und Eindringbarkeit derselben und die strukturelle Beeinflussung sowohl der karyoplasmatischen als auch zytoplasmatischen Zellbestandteile besondere Rücksicht genommen.
3. Die Pollenmutterzellen erweisen sich destilliertem Wasser sowie wässrigen Lösungen verschiedenartiger Chemikalien gegenüber bedeutend empfindlicher als die Wurzelzellen, was besonders bei karyoplasmatischen Strukturelementen deutlich hervortritt.
4. Das Karyotin der Pollenmutterzellen zeigt sich durch NaCl und Na₂SO₃ leichter löslich bzw. exosmierbar als dasselbe von Wurzelzellen.
5. Die Fixierungskonzentration und wirksame Konzentration für erprobte Chemikalien werden bei beiden Zellarten vergleichend tabellarisch zusammengestellt, wobei das numerische Verhältnis des Wirksamkeitsminimums zwischen beiden Zellarten besonders hervorgehoben wird.
6. Aus den Versuchen tritt höchstwahrscheinlich hervor, dass die Permeabilität des Protoplasmas für verschiedene Chemikalien bei einzelnen Mitosenstadien verschieden ausfällt.
7. Als Nekroformen wurden Strukturzerstörung, diffuse Färbbarkeit ganzer Zellstrukturen, Zytoplasmaschrumpfung, Abrundung und aggregative Tendenz der Chromosomen und Spiegelfärbung der Chromosomen und des Nukleolus ausführlich besprochen.
8. Verschiedenheit der Strukturen des Zytoplasmas und der Spindelsubstanz richtet sich wesentlich nach der Menge und Verteilungsweise konservierter Plasmagrundsubstanz, also mutmasslich nach dem Quellungsgrad des Protoplasmas.
9. Mitosenanomalien sind entweder auf die zeitliche oder die räumliche Störung normalen Chromosomenverhaltens zurückführbar. Bei dem chemischen Eingriffe kommt die erste Art der Mitosenstörung relativ selten vor.
10. Eine Mehrzahl der beobachteten Mitosenanomalien lassen sich von der nach dispersiver Richtung hin stattfindenden Verteilungsmodifikation der Chromosomen ableiten.
11. Auch bei den Pollenmutterzellen wird der Zytokinesenvorgang bei der Mannigfaltigkeit der Mitosenanomalien verhältnismässig selten angegriffen.
12. Weitere Beispiele für die Korrelation der Strukturmodifikationen untereinander werden angeführt; damit hat die angenommene Gegensätzlichkeit der kolloidalen Veränderungen im Protoplasma zwischen Metabiose und Nekrobiose weitere Bestätigung gefunden.

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1. Die rundliche Gestalt der Plastiden von Hydrilla verticillata ist mit CARNOYschem oder Sublimat-Alkohol-Gemisch naturgetreu fixierbar.
2. Sowohl bei den Blattanlagen als auch im Vegetationskegel lasst sie sich in den Meristemzellen immer nachweisen.
3. Während der Karyokinese verteilen sich die Plastiden in einer Zelle in zwei Gruppen, so dass jede Gruppe in jede Tochterzelle übergetragen wird.
4. Die hantelförmigen Teilungsfiguren der Plastiden sind während der Karyokinese nicht sichtbar.
5. Nachdem die Kern- und Zellteilung zur Vollendung gekom-men sind, beginnen sic sich durch Teilung intensiv zu vermehren.
6. Die Neubildung der Plastiden aus Chondriosomen wurde bei Hydrilla verticillata weder in lebendem Zustund noch bei fixiertem Textfig. 1. Schematische Darstellung der fixierten Plastiden: (a) durch CARNOYsches, (b) CHAMPYsches und (c) REGAUDsches Gemisch fixiertes Bild. Material festgestellt.
7. Durch die Chondriosomen fixierenden Flüssigkeiten, so z.B. REGAUDSches oder CHAMPYsches Gemisch werden die rundlichen Plastiden beträchtlich verunstaltet.
8. Bei der Fixierung mit CHAMPYschem Gemisch zeigen die Plastiden eine fadenförmige Gestalt, die mit deren typischer Chondriosomen von MEVES vollig übereinstimmt.
9. Bei REGAUDschem Gemisch treten die langgestreckten, mit verdickten Enden versehenen Gebilde hervor, welche solchen ganz ähnlich aussehen, wie sie von GUILLIERMOND, ALVARADO u. a. als Übergangsformen von Chondriosomen zu Plastiden angesehen werden.
10. Diese Verunstaltung der Plastiden durch Fixiermittel wird vorzüglich bei 2-4-stündiger Fixierungsdauer hervorgerufen.

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1. In the heterotypic prophase of the pollen mother cells in Carica papaya, Myrica rubra and Aucuba japonica, achromatic threads are all single in nature showing no parallel arrangement. In Beta vulgaris nucleolar budding is observed in the same stage.
2. End-to-end connection of univalent chromosomes is visible in the prophase of the pollen mother cells in all four species studied, so that the mode of gemini-formation is telosyndetic.
3. The haploid number of chromosomes is counted as follows: Carica papaya …… 9 Myrica rubra …… 8 Aucuba japonica …… 16 Beta vulgaris …… 9
4. The diploid number of chromosomes in Carica papaya is 18.
5. No sex chromosomes are found in the male of three dioecious plants, Carica papaya, Myrica rubra and Aucuba japonica.
6. The axes of both homotypic spindles in each of four species observed may be located in various angles to each other, namely they are parallel, perpendicular or oblique to each other.
7. Pollen tetrads are formed in all cases by the aid of protoplasmic furrowings instead of cell plates. The furrowing process may be initiated at interkinesis.
8. Tetraploid number of chromosomes is often found in the tapetal cells of Carica papaya.
9. In the postsynaptic prophase of Beta vulgaris three kinds of bivalent chromosomes can be distinguished, i. e. 4 rings, 4 rods and one small v-shaped one.

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1. There is no evidence whatever of parallel threads or of pairing of thicker portions of the threads composing the synaptic knot as observed in Oe. Lamarckiana by BOEDIJN.
2. Just before or in the second contraction the threads become differentiated into thicker and thinner portions. Time former grow in size and become univalent chromosomes.
3. A large closed circle of fourteen chromosomes is found at late prophase, which seems to be normally present in this species. Chromosomes composing the circle are joined end to end to one another.
4. The mode of gemini-formation in Oe. sinuata is telosyndetic.
5. There is a tendency for adjacent chromosomes forming a circle to become attached in pairs. Diakinesis is not entirely absent in this species.
6. At metaphase, chromosomes are brought to the equatorial region, the appearance being zigzag as seen from the side. This zigzag arrangement may be due to the mode of separation of chromosomes, that is, alternate chromosomes in the circle pass to the same pole.
7. The behaviour of chromosomes in separation is generally normal, though irregularities may occur to some extent.
8. The second meiotic division is entirely regular.
9. Pollen tetrads are formed by the method of furrowing.
10. The flowing of substance (caryotin ?) from nucleolus into chromosomes, as CLELAND assumes, is not likely to occur in Oe. sinuata.
11. The haploid and diploid numbers of chromosomes in this species are seven and fourteen respectively.

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1. In F₁ plant of Papaver somniferum L. var. glabrum BOIS. ×P. nudicaule L. the orange color of the petal of P. nudicaule dominated over the color of the petal of P. somniferum var. glabrum, hairy to glaucous, entire to laciniated, single to double, but perennial was recessive to annual.
2. Such dominant characters were eliminated in almost all individuals of S₄ plants of back-crossed F₂ plants, and the characters of P. somniferum var. glabrum were restituted among them.
3. The chromosome number of F₁ plants was 18, viz. the sum of the haploid chromosome numbers of both parents. Among these chromosomes 6 or 8 chromosomes only mated to form gemini in the meiosis of the pollen mother-cells and the rest remained as unpaired univalent chromosomes.
3. Out of 3 examined individuals of back-crossed F₂ plant, one had 11 bivalent chromosomes and 7 univalent chromosomes, another had 11 bivalent and 6 univalent chromosomes, and the remaining one 11 bivalent and 5 univalent chromosomes.
4. The univalent chromosomes were eliminated largely in F₃ individuals. Out of 122 individuals, in which the chromosome numbers were determined, 82 individuals showed 11 bivalent chromosomes only.
5. In 42 individuals which had more than 11 bivalent chromosomes, the largest number of univalent chromosomes was 4.
6. The parallel eliminations between the paternal characters and univalent chromosomes, and parallel restitution between the maternal characters and parasyndesis indicate that the univalent chromosomes belonged mostly to P. nudicaule L.
7. The large deviation in the segregation of F₃ plants may be ascribed to the irregular behavior of chromosomes in meiosis, but in addition the writer expects interchanges of genes concerning these characters.
8. There was one plant whose petals had red spots which never observed in their previous generations.

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By studying the seed- or anther-bearing leaves of Ginkgo biloba, and comparing them with the normal flowers, the writer came to the following conclusions:
1. Seed- and anther-bearing leaves are senile forms.
2. The so-called collar of seed and knob-like terminal scales of anther are the residual portion of the lamina of the reproductive leaf.
3. Seed-bearing leaves are homologous to normal seeds.
4. Normal seed stalk is a floral axis.
5. Ovule and anther are phyllcme organs.

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The bristles on the flower stalk are produced by duplicate factors, though they may exhibit some fluctuation in the manifestation of their phenotype and give more or less a higher ratio of the smooth stalk in the segregating generation. The crapy corolla behaves as a simple recessive to the normal condition, but its ratio in the segregating generation is almost always somewhat lower than the simplest requirement. The serrate petal acts as a dominant over the entire one, while its segregating ratio exhibited much variability in our experiments. We have some evidence to recognize the occurrence of modifiers affecting the degree of serration, though the F₃ examination showed the fact the main part of variability is due to the environmental condition. The double flower is a recessive character to the single, but its segregation is usually very low in proportion. The genetic nature of the double, therefore, is not simple. Besides the ordinary recessive double, we have met with a dominant one, which gives quite contrary result in crossing with a single.

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