. The effects of inanition and malnutrition upon growth and structure . Spermatogonia ^1 w>xVacuole Syncytium x^T^^Hf Inclusions^^--^ Fig. 10.—Ectoderm cells from starving Hydra fusca. Highly magnified. The cells are separated by large interstitial spaces. The cytoplasm is scanty; the nuclei relatively large. A group of the persistent sex-cells (spermatogonia) is shown. (After Schultz '06.) Fig. 11.—Entoderm cells from starving Hydra fusca. (After Schultz '06.) Highly magnified. The cells have fused into an irregular syncytium, containing vacuoles, pigment granules and inclusions. The free
. The effects of inanition and malnutrition upon growth and structure . Spermatogonia ^1 w>xVacuole Syncytium x^T^^Hf Inclusions^^--^ Fig. 10.—Ectoderm cells from starving Hydra fusca. Highly magnified. The cells are separated by large interstitial spaces. The cytoplasm is scanty; the nuclei relatively large. A group of the persistent sex-cells (spermatogonia) is shown. (After Schultz '06.) Fig. 11.—Entoderm cells from starving Hydra fusca. (After Schultz '06.) Highly magnified. The cells have fused into an irregular syncytium, containing vacuoles, pigment granules and inclusions. The free surfaces of the cells show irregular processes. In the body ectoderm (Fig. 10), there is great variation in the resistance of different cells. The epithelium-muscle cells remain flatly extended, with progressive loss of plasma until the nucleus is barely covered. The cytoplasm usually becomes vacuolated. The mematoblasts disappear entirely. Other cells, however, may retain much cytoplasm, sometimes with gigantic nuclei. The gland cells of the foot remain apparently unchanged. The development of the testes (as above mentioned, Fig. 10) proceeds in spite of inanition, "Oder richtiger gerade infolge des ; " Je mehr das betreffende Tier reduziert war, desto weiter war meistens die Reife der Testikel geschritten. Auch wimmelten meine Aquarien, wo ich die hungernde Tiere hielt, bald von Sperma- tozoen. Doch wachsen die Testikel nie zu jenen mammaformigen Gebilden, wie sie gewohnlich bei Hydra fusca erscheinen. Sie blieben weit kleiner und bildeten nur geringere Anhaufung unter dem Ectoderm. Eine Reifung der Ovarien beobachtete ich ; Of the entoderm in Hydra, the so-called gland cells show no morphological changes, although they decrease in number. The intestinal epithelium, how-
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Keywords: ., bookcentury1900, bookdecade1920, bookpublis, booksubjectnutrition
