. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 148 R. R. HUMPHREY. the growth and divisions of its spermatocytes, the slender caudal appendage is naturally in obvious contrast as to size (Fig. 4). In the fall, after extrusion of the spermatozoa, the testis proper is greatly reduced in diameter; the appendage, meanwhile, has become considerably enlarged. During the winter, as a result, the testis appears of more nearly uniform diameter throughout, as in Fig. I, with little or no indication of the caudal reduction so striking in the preceding summer. Nevertheless, in the s
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 148 R. R. HUMPHREY. the growth and divisions of its spermatocytes, the slender caudal appendage is naturally in obvious contrast as to size (Fig. 4). In the fall, after extrusion of the spermatozoa, the testis proper is greatly reduced in diameter; the appendage, meanwhile, has become considerably enlarged. During the winter, as a result, the testis appears of more nearly uniform diameter throughout, as in Fig. I, with little or no indication of the caudal reduction so striking in the preceding summer. Nevertheless, in the spring the appendage once more makes its FIG. 8. Caudal third of the testis of Plethodon gliilinostts in late June. Semi- diagrammatic. The reduction in size of the lobules of the caudal appendage is strikingly shown; but little debris from degenerating cells now remains. Though the body of the testis at this season contains transforming spermatids, the lobules of the appendage show only occasional germ cells other than their apical spcrma- togonia. , transforming spermatids; , longitudinal collecting duct, central in position, surrounded by connective tissue; , primary spermatogonium (residual spermatogonium) of lobule apex; d., nuclear debris from recently de- generating germ cells; , interstitial cells; sp., group of spermatids; 5., a primary spermatocyte. Examined in sections, the appendage of a male killed in early June is found to be traversed by the central collecting duct of the. 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; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass.
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