. The effects of inanition and malnutrition upon growth and structure . Fig. 4.—Paramecium after eight days of inanition. The characteristic crescent-shaped curvature of the body appears in this case. The macronucleus (N) and micronucleus (n) have emigrated to the anterior end of the body. Fig. 5.—Paramecium after nine days of inanition. The macronucleus has divided into two spheroidal bodies (N, N), the micronucleus (n) remaining undivided. Fig. 6.—Paramecium after twelve days of inanition, showing the degeneration vacuoles (), considered characteristic by Wallengren ('02) but not by Lips
. The effects of inanition and malnutrition upon growth and structure . Fig. 4.—Paramecium after eight days of inanition. The characteristic crescent-shaped curvature of the body appears in this case. The macronucleus (N) and micronucleus (n) have emigrated to the anterior end of the body. Fig. 5.—Paramecium after nine days of inanition. The macronucleus has divided into two spheroidal bodies (N, N), the micronucleus (n) remaining undivided. Fig. 6.—Paramecium after twelve days of inanition, showing the degeneration vacuoles (), considered characteristic by Wallengren ('02) but not by Lipska ('10). one-half in the various dimensions, which is somewhat greater than the average decrease obtained by Jennings, but not very different from that of Kasanzeff and Wallengren. A decrease of one-half in dimensions would correspond to a loss of seven-eighths (87^ per cent) in volume. By a curious error, Lipska confuses dimensions and volume, concluding that "II meurt lorsqu'il a perdu a peu pres la moitie de son volume ; In the endoplasm of the starving Paramecium, Lipska found, in agreement with all previous investigators, a progessive disappearance of the food-vacuoles, with corresponding increasing transparency of the cytoplasm. The "excretion crystals" become more clearly visible, but decreased in size and number (as previously noted in P. caudatum by Schewiakoff '94). While apparently all previous observers (including Kolsch '02) have described a marked and progres- sive vacuolation of the endoplasm (cf. Fig. 6), Lipska could not find even a single case of such vacuolation during inanition. She found the vacuolation well marked in old cultures with the ordinary technique, however, and concluded
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