. The cell in development and inheritance. Cells. 44 ci:x/:KAf. sk-i-yjc// of jiie microsomes in certain cases. In many Protozoa, for example, a fine alveolar structure nia\ l>c seen in the living protoplasm ; and Flem- ming" as well as nian\- later observers has clearly seen fibrillar struc- tures in the li\ing cells t)l cartilage, epithelium connective-tissue, and some other animal cells ( Fig. 9). Mikosch, also, has recently described ^i,'vv?/////<?'/'threads in living plant-cells. Almost cc[uall\- conclusixe is the beautifully regular arrangement of the fibrilke in ciliat
. The cell in development and inheritance. Cells. 44 ci:x/:KAf. sk-i-yjc// of jiie microsomes in certain cases. In many Protozoa, for example, a fine alveolar structure nia\ l>c seen in the living protoplasm ; and Flem- ming" as well as nian\- later observers has clearly seen fibrillar struc- tures in the li\ing cells t)l cartilage, epithelium connective-tissue, and some other animal cells ( Fig. 9). Mikosch, also, has recently described ^i,'vv?/////<?'/'threads in living plant-cells. Almost cc[uall\- conclusixe is the beautifully regular arrangement of the fibrilke in ciliated cells (Fig. 17, P^ngelmann), in muscle-fibres and nerve-fibres, and especially in the mitotic figure of dividing cells 9J- •4^4 ^<:S« •••?'«- '.f'*». Fig. 18. — Cells of the pancreas in Amphibia. [MATHEWS.] A-C. Necturiis; D. Rana. A and B represent two stages of the "loaded "cell, showing zynnogen-granules in the peripheral and fibrillar structures in the basal part of the cell. C shows cells after discharge of the granule-material and invasion of the entire cell by fibrillae. In D por- tions of the fibrillar material are coiled to form the mitosome (" paranucleus " or " Nebenkern "). (Figs. 21, 31), where they are likewise more or less clearly visible in life. A very convincing case is afforded by the pancreas-cells of Nectnrus, which Mathews has carefully studied in my laboratory. Here the thread-work consists of long, conspicuous, definite fibrillae, some of which may under certain conditions be wound up more or less closely in a spiral mass to form the so-called Nebenkern. In all these cases it is impossible to regard the thread-work as an accidental coagulation-product. In the case of echinoderm eggs, I have made ('99) a critical comparison of the living structure, as seen under powers. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectcells, bookyear1906
