. La cyclopaedia d'anatomie et physiologie. Anatomie ; physiologie ; Zoologie. La reproduction, de légumes Légumes (ovule). 219 brane.* Lorsque deux frondes sont sur le point de con- jugate, ils se placent parallèlement et op- de composites eux, avec leurs visages concaves sur- face. Nous aimerions maintenant que la membrane cellulaire partiellement fait des concessions en ligne ci-dessus mentionné, les deux moitiés de chaque Clostcrium séparant légèrement sur le côté opposé à ses concitoyens, mais rester au contact de l'autre sicle. Les ouvertures sont observés sous peu d'être occupés par des projections de coussin de la membrane externe, dans lequel sque

• Contributeur: The Book Worm
• ID de l’image: RD5MMJ
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. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. REPRODUCTION, VEGETABLE (VEGETABLE OVUM). 219 brane.* When two fronds are about to con- jugate, they place themselves parallel and op- posite to each other, with their concave sur- faces facing. We next remark that the cell membrane partially gives way at the line above mentioned, the two halves of each Clostcrium separating slightly on the side opposite its fellow, but remaining in contact on the other sicle. The openings are soon observed to be occupied by cushion-like projections of the in- ternal membrane, which squeeze out between the valves. From the fact that the cavity of the internal membrane is double, or rather that each halfof the Closterium possesses an independent primordial membrane, it follows that each of the projections above mentioned consists of two distinct sacculi. Soon the two double cushions come in contact; they are at first perfectly colourless, but shortly afterwards become filled with green granular matter, and press so closely together as to be no longer distinguishable. It is next observed that from the junction of the four sacculi, two canals have resulted, each of which soon swells out in a hemispherical form, corresponding to Fig. 136.. Conjugation of Closterium. The two fronds are connected by two delicate tubes? each of which contains a hemispherical germ- cell closely invested by its membrane. The two germ-cells, which are in opposition by their flat surfaces, appear as one. About 40 diam. that of a mass of green granular matter which now occupies its cavity. This mass is soon in- vested by a delicate membrane, which, in the progress of development, thickens and pre- sents an uneven surface. The two bodies which thus take their origin are the germ cells. They soon become free from the struc- ture in which they were formed, and, according to Morren, display for about fifteen minutes after their escape an active motion. After this period, the motion ceases, a

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