. The effects of inanition and malnutrition upon growth and structure. Starvation; Nutrition. Bell rim lsS4 Arnvj" F1$.D. Arms" F4I4 Lateral view, natural Fig. 12.—Normal medusa of the jellyfish, Cassiopea xamachana. size. (After Mayer '14.) Fig. 13.—Medusa of the jellyfish, Cassiopea xamachana, starved 41 days in darkness, with loss of about 96 per cent in weight. Lateral view, natural size. (After Mayer '14.) Fig. 14.—Same as Fig. 13, but magnified to original size, for comparison with Fig. 12, to show more clearly the change in form undergone by the jellyfish Cassiopea duri
. The effects of inanition and malnutrition upon growth and structure. Starvation; Nutrition. Bell rim lsS4 Arnvj" F1$.D. Arms" F4I4 Lateral view, natural Fig. 12.—Normal medusa of the jellyfish, Cassiopea xamachana. size. (After Mayer '14.) Fig. 13.—Medusa of the jellyfish, Cassiopea xamachana, starved 41 days in darkness, with loss of about 96 per cent in weight. Lateral view, natural size. (After Mayer '14.) Fig. 14.—Same as Fig. 13, but magnified to original size, for comparison with Fig. 12, to show more clearly the change in form undergone by the jellyfish Cassiopea during inanition. Note the relatively small bell (umbrella) with upturned rim, and the relatively large arms with rudimentary tentacles. In six weeks of inanition, with final loss of over 96 per cent in body weight, there are likewise progressive changes in body form (Figs. 12, 13, 14). The bell-rim becomes shrunken and bent upward, and the arms atrophic. The mouths become closed by coalescence in about three weeks, so that subsequent recovery by refeeding is impossible. The cells are reduced in size; many become fused into a syncytial condition or degenerate and disappear. The gelatinous substance, which forms about 95 per cent of the organism, is greatly reduced in amount and becomes vacuolated. The commensal green algae become crowded in the diminutive starving Cassiopea, and ordinarily most of them escape from the body; but if the experiment is conducted in darkness most of the algae degenerate, and die, although a few may persist and regenerate a new supply upon refeeding. Hatai ('17) confirmed Mayer's formula for the loss in weight of starving Cassiopea (after the first day), but found little change in the relative weights of the mouth organs, umbrella and velar lobes. In connection with his experiments on partial inanition with various salt deficiencies, Herbst ('97) made a few incidental observations on Cotylorhiza tuberculata. Phosphorus was found necessary to enable
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