Science-gossip . is the presence of very fine nuclei in thecells of the spongy parenchyma of a size which onerarely sees in other plant-cells. A Conjugating Yeast.—Under certain con-ditions of existence Saccharomyces seems topossess the power of rejuvenescence by meansof the process of conjugation. In a paper by T. P. Barker, B. A., in Proc. Roy. Soc.,july1901, the various experiments on this subject areexplained at some length. The essential pointsare that vigorously growing cells were observed ina drop of distilled water; the contents of a pairof cells first of all became vacuolated, a
Science-gossip . is the presence of very fine nuclei in thecells of the spongy parenchyma of a size which onerarely sees in other plant-cells. A Conjugating Yeast.—Under certain con-ditions of existence Saccharomyces seems topossess the power of rejuvenescence by meansof the process of conjugation. In a paper by T. P. Barker, B. A., in Proc. Roy. Soc.,july1901, the various experiments on this subject areexplained at some length. The essential pointsare that vigorously growing cells were observed ina drop of distilled water; the contents of a pairof cells first of all became vacuolated, and a beak-like process was put out by each cell. These j)ro-cesses met and fused, and the protoplasmic contentscommunicated through the passage thus a few hours the protoplasm began to contractand small round masses formed, which subse-quently developed into spores. OosPHERES OF PiNUS.—On examining a longi-tudinal section taken through the embryo-sacof some gymnosperms (Pinvs nylredris and nk. Fra 3. Sections of Austrian PI^E-ovuLl•:s. Vratrn hii Harold A. Haia, from Photo-micrograph hiiA. E. Powell A. LoNaiTunix.\L section through three , SHOWING OOSPHERFS ; IN THE MIDDLE ONE, DIVISIONHAS COMMffNCED. ni. Apex of embryo-sac. a. Archegonium. o. Oosphtre, showingcentral nucleus and numerous vacuoles, c, Oanal. B. High-power dbawing of receptive spot. o. Oospliere. h. Vacuoles, c. Canal, r. Portion of separatedprotoplasm forming the receptive spot. anstraea), one cannot fail to notice the relativelylarge size of the archegonia and their containedcorpuscula or oospheres. The protoplasm of theselatter is very granular, and there are usually a large number of good-sized vacuoles scatteredthroughout its substance. The nucleus is, so tospeak, immense, and is very clear, with a smallnucleolus near the centre (see fig. 3). An import-ant point to be observed about the time whenfertilisation commences is the existence at the-micropylar extremity of the oos
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