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They had analysed soils, estimated the rainfall, and examined the germination of seeds; they understood such mysterious terms as bacteria, protozoa, cotyledons, trenching and ridging, cross-fertilization and spermatozoids, and had some elementary acquaintance with the theory of the rotation of crops.
Thus, for instance, it is shown that the egg of the sea-urchin may be “stimulated” to development, not exclusively by the fertilising sperm, but even by a simple chemical agent, or that spermatozoids which are seeking the ovum to be fertilised may be attracted by malic acid.
Others permanently formed of some multiple of four; the highest forms made up of compact, numerous, more or less closely joined cells. Reproduction: by cell division, by the conversion of the cell contents into zoospores, and by resting spores, formed sometimes after conjugation; in other cases, probably, by fecundation by spermatozoids. All the unicellular algae are included under this head.
At the egg-layer's will, the receptacle bestows a tiny drop of its contents upon the matured ovule, when it reaches the oviduct, and you have a female egg; or else it withholds its spermatozoids and you have an egg that remains male, as it was at first. I readily admit it: the theory is very simple, lucid and seductive. But is it correct? That is another question.
Reproduction by division, or by single cells being converted into new families; and by resting spores formed from some of the cells after impregnation by spermatozoids formed from the contents of other cells of the same family. Plate IX. Large group of malaria plants, Gemiasma verdans, collected at 165th Street, east of 10th Avenue, New York, in October, 1881, by Dr.
Resting spores produced after fertilization either by conjugation or impregnation. 2. Spermatozoids. 3. Zeospores; 2, 4, or multiciliated active automobile cells gonidia discharged from the mother cells or plants without impregnation, and germinating directly. There is also another increase by cell division. Lemaneae.
Fructification: zoospores produced from the cell contents of the filaments; resting spores formed from the contents of particular cells after impregnation by ciliated spermatozoids produced in distinct antheridial cells. Coleochaetae. Confervaceae. Not conjugating. Zygnemaceae. Aquatic filamentous plants, without evident gelatine, composed of series of cylindrical cells, straight or curved.
In the, field of original scientific research is the famous bacteriologist, Dr. Kitazato. Less widely known perhaps, but none the less truly original explorers in the field of science, are Messrs. Hirase and Ikeno, whose discoveries of spermatozoids in Ginko and Cycas have no little value for botanists, especially in the development of the theory of certain forms of fertilization.
Cell contents uniform, dense, cell division accompanied by circumscissile debiscence of the parent cell, producing rings on the filaments. Reproduction by zoospores formed of the whole contents of a cell, with a crown of numerous cilia; resting spores formed in sporangial cells after fecundation by ciliated spermatozoids formed in antheridial cells.
Cf. Is the organ really absent? Or was there want of skill on my part? I lean towards want of skill and admit that all the game-hunting and honey-gathering Hymenoptera possess a seminal receptacle, which can be recognized by its contents, a quantity of spiral spermatozoids whirling and twisting on the slide of the microscope.
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