. The cell in development and inheritance. Cells; Cells. 2 INTRODUCTION of the Lamarckian period gave little heed to the finer details of internal organization. They were concerned mainly with the more obvious characters of plants and animals â their forms, colours, habits, distribution, their anatomy and embryonic development â and with the systems of classification based upon such characters ; and long afterwards it was, in the main, the study of like characters with reference to their historical origin that led Darwin-to his splen- %'^^ $>i i^) y^M^M}-p -^< . -if' .â ,<^-''4 a; ^.
. The cell in development and inheritance. Cells; Cells. 2 INTRODUCTION of the Lamarckian period gave little heed to the finer details of internal organization. They were concerned mainly with the more obvious characters of plants and animals â their forms, colours, habits, distribution, their anatomy and embryonic development â and with the systems of classification based upon such characters ; and long afterwards it was, in the main, the study of like characters with reference to their historical origin that led Darwin-to his splen- %'^^ $>i i^) y^M^M}-p -^< . -if' .â ,<^-''4 a; ^. <$ Fig. I.âA portion of the epidermis of a larval salamander {Amblystomd) as seen in slightly oblique horizontal section, enlarged 550 diameters. Most of the cells are polygonal in form, con- tain large nuclei, and are connected by delicate protoplasmic bridges. Above j; is a branched, dark pigment-cell that has crept up from the deeper layers and lies between the epidermal cells. Three of the latter are undergoing division, the earliest stage {spireme) at a, a later stage (mitotic figure in the anaphase) at i5, showing the chromosomes, and a final stage {telophase'), showing fission of the cell-body, to the right. did trium])hs. The study of microscopical anatomy, on which the cell-theory was based, lay in a different field. It was begun and long carried forward with no thought of its bearing on the origin of living- forms ; and even at the present day the fundamental problems of organization, with which the cell-theory deals, are far less accessible to historical inquiry than those suggested by the more obvious external characters of plants and animals. Only within a few Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Wilson, Edmund B. (Edmund Beecher), 1856-1939. New York : The Macmillan co
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectcells, bookyear1896
