. Darwin, and after Darwin. An exposition of the Darwinian theory and a discussion of post-Darwinian questions. Evolution; Heredity. Embryology. 113 beautifully ordered, that to my mind they constitute the most wonderful—if not also the most suggestive —which have ever been revealed by microscopical re- search. It is needless to say that I refer to the phenomena of karyokinesis. A few pages further on they will be described more fully. For our present purposes it is sufficient to give merely a pictorial. Fig. 29.—Successive stages in the division of the ovum, or egg-cell, of a worm. (After Str
. Darwin, and after Darwin. An exposition of the Darwinian theory and a discussion of post-Darwinian questions. Evolution; Heredity. Embryology. 113 beautifully ordered, that to my mind they constitute the most wonderful—if not also the most suggestive —which have ever been revealed by microscopical re- search. It is needless to say that I refer to the phenomena of karyokinesis. A few pages further on they will be described more fully. For our present purposes it is sufficient to give merely a pictorial. Fig. 29.—Successive stages in the division of the ovum, or egg-cell, of a worm. (After Strasburger.) a to d show the changes taking place in the nucleus and surrounding cell-contents, which result in the first segmentation of the ovum 2X e; f and g show a repetition of these changes in each of the two resulting cells, leading to the second seg- mentation stage at h. illustration of their successive phases ; for a glance at such a representation serves to reveal the only point to which attention has now to be drawn—namely, the immense complexity of the processes in question, and therefore the contrast which they furnish to the simple (or "direct") division of the nucleus preparatory to cell-division in the unicellular organisms. Here, then. 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 Romanes, George John, 1848-1894. Chicago The Open Court Pub. Co
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