From 1960 to 1961, studies on decapitation and translocation of assimilates of rape (Brassica napella Chaix.) have been carried out at Shanghai. The results of these experiments may be summarised as follows. Since decapitation destroyed “apical dominance”, it resulted changes in plant form. The growth rates of the 1st, 2nd and 3rd branches accelerated. The length and weight of the side branches and the number of capsules on the branches increased. But the increase in number of capsules on branches could not compensate the decrease in number of capsules in the decapitated parts; the yield of rape was lower in the treated plants. At the shooting stage, the major part of the assimilates produced in the leaves was translocated to stems, when the leaves were supplied with C14O2 72.8% of the total radioactivity appeared in stem, 12.6% in buds, 13.8% in roots and 0.7% in leaves. There was a localization of assimilates between the leaves and their auxillary buds, and among the phyllotaxically related parts. Decapitation modified the numerical ratio of the distribution without changing its essential order.

1. In agreement with the observations of earlier workers the writer has found that the carpospores of Nemalion helminthoides (Valley) Bate. v. vermiculare (Sur.) Tseng (materials obtained along the coast of Tsingtao) give rise to prostrate filaments which are uniseriate and branched, each cell with a single stellate chromatophore. 2. Algologists generally believe that, in Nemalion, the erect fronds are emerged directly from prostrate filaments grown from carpospores. In contrast to this assumption, the writer repeatedly found that the erect fronds of N. helminthoides var. vermiculare were able to reappear in nature where the prostrate filaments (and any other algal inhabitant) had been exterminated previously by treating with lime-water in early spring. This finding strongly indicates that these erect fronds were not formed directly from the prostrate filaments arising from carpospores of the previous year. 3. The prostrate filaments (arising from carpospores), either cultivated in the laboratory or found in the field, produce monospores from early spring to early summer. The sporangia are either sessile or unicellularly stalked, growing on the cells of the middle parts of the filaments. They germinate again into protrate filamentous systems which are morphologically extremely similar to those grown from carpospores. This prostrate system is evidently an important (if not the only) source from which the erect fronds of Nemalion arise. 4. Since the early spring of 1960, the writer has periodically sought for the monospores from the following materials gathered in nature: 1) prostrate filaments; 2) juvenile erect thalli free from bases and prostrate filaments. It is found that only the prostrate filaments are capable of producing monospores. 5. On several occasions the writer observed that the prostrate filaments originating from the monospores aggregated in such a manner as to indicate possibilities of giving rise to erect fronds. However, more careful observations are needed to arrive at a definite conclusion.

Activities of terminal oxidases involved in the respiration of rice seedlings (variety Yinfang) were studied with respect to their adaptation to low oxygen tensions. Four–day old seedlings grown on quartz sand moistened with Espino solution were used as material. The results of these experiments are summarized below. 1. Ascorbic acid oxidase and cytochrorne oxidase, but not polyphenol oxidase are found in the tissue extracts of the seedlings. The activities of these enzymes differ in different organs. Higher cytochrome oxidase activity is found in coleoptiles and leaves while in the root, ascorbic acid oxidase activity is higher than that of cytochrome oxidase. 2. Inhibition experiments with CO, sodium azide and dieca indicate that the metal-containing oxidases (cytochrome and ascorbic acid oxidases) comprise about one half of the total terminal oxidase activity, the remainder is presumably due to that of the flavo-proteins which are insensitive to the actions of these inhibitors. The activities of the 2 metal enzymes, cytochrome and ascorbic acid oxidases are equally intensive, each comprises ¼ of the total terminal oxidase activity of the entire seedling. 3. In seedlings which have been adapted for 24 hours under 21%, 10%, 5% and 1% partial pressures of oxygen, the relative intensities of ascorbic acid oxidase activity is unchanged while the activity of cytochrome oxidase is very much increased, with a corresponding decrease in flavoprotein activity. 4. Under submerged condition, there is an increase in cytochrome oxidase activity in the seedlings and a corresponding decrease in flavo-protein activity much as that which is observed under low oxygen tensions. Withdrawal of the water layer after 24 hours of submergence reversed the situation, so that there is evidence of de-adaptation in these enzyme activities. 5. Low oxygen tension is unfavorable for seedling growth. Under such conditions the dry weight of the seedlings decreases. There is an apparent correlation between this effect of low oxygen on growth and the degree of activity of cytochrome oxidase. Relatively long periods of oxygen depletion are definitely harmful to seedling growth, and it is concluded that growth in the rice seedlings is an oxygen-requiring process.

Eucommia ulmoides Oliv. is a deciduous elm like tree, as an ornamental cultivated in China. Many works on the vegetative anatomy of the Eucommia had been carried out very early, but the floral development was seldom known. The present study was undertaken with a view to provide a description of the sporogenesis and gametophyte development of this plant. Flower buds in various stages of delopement and open flowers of the plant were collected from trees growing in the vicinity of Nanking and fixed in FAA. The material was imbedded in paraffin and sections, 8–10 μm in thickness were cut, stained either in Heidenhains iron-alum heamatoxylin or with safranin and crystal violet. In the first collection on 24th March, the sporogeneous cells did not round off or separated from each other. As the microspore mother cell arised from sporogeneus cell, the four lobes of each anther were fully enlarged. After the first reduction division of the microspore mother cell took place, no cell plate was laid down and the two daughter nuclei immediately took part in the second division. The arrangement of the tetrad in Eucommia is of tetrahedral type. The reduction division stage of microsporegenesis was found in material collected on 24th March. The pollination occurred at the end of March in 1954 at Nanking. The tapetal cells are uninucleate ories at first but through succeeding divisions, when the microspore mother cells are in synthesis, they become two- or four-nucleate. After the microspores have been separated, the tapetal cells get loose. A gradual diminution of cytoplasm proceeds simultaneously with the further growth of the pollen grains, and finally the contents are entirely used up. During pollination the nucleus of the microspore divided into two parts to form a large tube cell and a small generative cell. Then the pollen tubes stretched into the nucellus in the last two weeks of April. Meanwhile the generative cell has already been divided into two male nuclei. At this later stage, the tube nucleus was still in presence. But it is not the case in Ulmus (Shattuck, 1905). Two anatropus ovules arise from the inner surface of the ovary wall, and one of them aborted after fertilization. A single layer of integument arises from the chalazal end of the ovule by periclinal division. Parallal to formation of the integument a hypodermal cell of the nucellus is differentated as an archsporial cell. It is easily recognized by its large size and deeply staining characteristics. The hypodermal archesporial cell in the young nucellus divides to form a primary wall cell and a megaspore mother cell. Resulting from the successive divisions of the primary wall cell, a number of parietal cells situiate between the epidermal layer of the ovule and the megaspores. Therefore, the early development of nucellus belongs to Crassinuceltate type. But as the embryo sac enlarges the parietal cells aborte and thus the nucellus becomes simple nucellate. After megaspore mother cell forms linear tetrad of megaspores, the upper three degenerate progressively. Consequently, only the chalazai one develops into embryo-sac apparatus and thus monosporic type is conformed. The remaining megaspore undergoes two further divisions forming a typical eight nucleate megagametophyte. The mature embryo-sac, in general, consists of three antipodals, two polar nuclei, and three of the micropylar nuclei which are incorporated in cells to form the typical egg apparatus. And thus, the development of the megagametophyte of the species of Eucommia investigated indicates that this genus is of polygonium type somewhat differs from the Adoxa and Drusa types of the Ulmaceae in the Urticales.

A study of twelve species of bamboos, Pseudosasa amabilis (McClure) Keng f., Semiarundinaria Henryi McClure, Sinobambusa sp. (?), Dendrocalamus strictus (Roxb.) Nees, Bambusa lapidea McClure, Schizostachyum funghamii McClure, Bambusa textilis McClure, Bambusa pervariabilis McClure, Sinocalamus latiflorus (Munro) McClure, Sinocalamus sp., Lingnania Chungii (Mc- Clure) McClure, Lingnania sp., of Kwangtung Province has been undertaken subsequent to the previous descriptions of Phyllostachys pubescens, Ph. bambusoides, Ph. nigra var. Henonis, Brachystachyum densiflorum, Chimonobambusa quadrangularis, Pseudosasa japonica, Indocalamus Migoi, Shibataea chinensis, Pleioblastus amarus, Sinocalamus Oldhami, Bambusa multiplex, B. multiplex var. nana. The comparative anatomy of such species has been extensively investigated and a more or less comprehensive key to such is presented in aid to their identifications.

This paper is an investigation of the modes of multiplication of free nuclei of the endosperm of wheat. It embodies 3 parts: 1. Mutual fusion of free nuclei, 2. Multiplication of free nuclei, 3. Mitotic and non-mitotic division. 1. Mutual fusion of free nuclei takes place not only during the resting stage, but also at any time when the division is going on. Polyploid free nuclei are due to the mutual fusion of free nuclei. 2. In the endosperm of wheat, polyploid free nuclei are multiplied by the same method as triploid free nuclei, viz., by means of mitotic and non-mitotic divisions. 3. The manner of mitotic division of polyploid free nuclei is the same as the normal. This is observed at the various stages. 4. The causes of the formation natural polyploidy may be various. Low temperature is a known factor. 5. Some free nuclei in anaphase and telophase of mitoses the chromosome bridges were occasionally observed. They may persist even in the resting stage. 6. when mitoses of the most of free nuclei in the whole endosperm are for some cause fail proceeding to completion, individual free nuclei cannot finish the division complete the anaphase and therefore the two groups of chromosomes are only a very short distance apart and form two daughter nuclei, very close together, at long last these finally unite into polyploid nucleus. 7. Some roundish bits, which are whithout structure and very similar to nucleoli in the form and size, are abstricted from pseudopodoid parts of amoeboid triploid and polyploid nuclei. Each bit grows into a normal nucleus. This is a hitherto unrecorded a method of non-mitotic multiplication for the plant cell. 8. Some tripoid and polyploid free nuclei show prophase, metaphase, anaphase or telophase in the structure, but then revert to non-mitotic division. This may be that due to some condition, Which prevents mitosis to go to completion. This phenomenon illustrates that both mitotic and non-mitotic divisions are closely associated. They can be interconvertible not only at the resting stage, but also at any time when cell division is going on.

Meiotic abnormalities in a number of varieties of cultivated rice, induced by rainy weather, and abnormal temperatures, have been described. The number of chromosomes varied in pollen mother cells. The meiotic behaviour of chromosomes as seen from the dividing pollen mother cells was irregular. The chromosomes usually lie scattered in the spindle. Laggards, stickness, elimination of chromosomes, unequal distribution of chromosomes in anaphase have also been described. Other meiotic irregularities comprised the formation of diploid pollen mother cells and multipolar spindles, failure of cytokinesis, and two or three spindles in one pollen mother cells.