. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 26 W. S. SUTTON. size. In other words, there are, in the ordinary chromosome group, not twenty-two but eleven sizes of chromosomes. The lettering in the figure will indicate the pairs in the smaller group where they are most clearly defined. Eightl generations of spermatogonia follow this one, and in each succeeding metaphase the same number and size-relations of chromosomes may be observed. This is shown in Figs. 2 and 3, representing different secondary spermatogonial generations, FIG. 2. FIG FIG. 2. Polar view of equa
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 26 W. S. SUTTON. size. In other words, there are, in the ordinary chromosome group, not twenty-two but eleven sizes of chromosomes. The lettering in the figure will indicate the pairs in the smaller group where they are most clearly defined. Eightl generations of spermatogonia follow this one, and in each succeeding metaphase the same number and size-relations of chromosomes may be observed. This is shown in Figs. 2 and 3, representing different secondary spermatogonial generations, FIG. 2. FIG FIG. 2. Polar view of equatorial plate in secondary spermatogonium of one of the earlier generations. (From section.) Fir,. 3. Oblique lateral view of equatorial plate of a secondary spermatogonium of one of the later generations. (From a smear-preparation.) Small chromosomes and accessory designated as in Fig. I. in each of which appears six small chromosomes and seventeen larger ones. In each of these also — especially in the case of the smaller group, the members of which, on account of their nearly spherical form, do not suffer the same degree of fore- shortening in the drawing as do many of their longer comrades — the paired relation may again be made out. Moreover, in the smaller group with its fewer members and greater size-differences, it is possible to see that the volume of the smallest pair (kK), for instance, in one cell bears approximately the same ratio to the homologous pair in another cell as does that of the largest (^/) of the 1 Based on estimates of the number of cells in a spermatocyst at the time of trans- formation to 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 Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952;
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
