24 



INANITION AND MALNUTRITION 



The body of Paramecium (as observed by Lipska) becomes progressively 

 smaller, with no change of form until the fourth day of inanition. In later 

 stages, it may become variously deformed — flattened dorsoventrally (Fig. 3), 

 later often crescent-shaped (Fig. 4) or pyriform (Fig. 2). The average data for 

 length and breadth in microns are as follows: normal Paramecium, 238 (length) 

 — 54 (breadth); starved and flattened, 124-28.5; starved and crescent-shaped, 

 136.8-28.8; starved and pyriform, 118-46. Thus there is a decrease of nearly 



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 

 (d.v.), 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 initial." 



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 



