62 LIBBIE H. HYMAN 



endoplasmic granules; but upon moving a needle point about 

 among these granules one finds that they are contained in a 

 viscous substance. I have not been able to observe the fate 

 of the nucleus but as it is never to be found among the extruded 

 granules, I conclude that it disintegrates with the protoplasm. 

 Figure 1 represents four stages in the disintegration of an 

 amoeba in molecular KNC. In a the amoeba is flowing in the 

 direction indicated by the external arrow ; the posterior end pre- 

 sents the corrugated appearance which is an invariable charac- 

 teristic of the amoebae with which I have worked and which I 

 shall refer to later. After the application of the cyanide, the 

 ectoplasm bursts at the point x in b, some of the endoplasm 



• 



Fig. 1 Disintegration of amoeba in molecular KNC. a, the amoeba is flow- 

 ing in the direction of the external arrow; b, after application of the cyanide, the 

 ectoplasm bursts at x; c, the endoplasm escapes from the rupture; d, disintegra- 

 tion has begun at the distal end of the pseudopodium and is proceeding as indi- 

 cated by the internal arrow. 



flows out, and the amoeba contracts slightly as a consequence. 

 The endoplasm continues to stream forth for a short time as 

 shown in c. Next the tip of the pseudopodium begins to disin- 

 tegrate and the disintegration proceeds down the axis of the 

 pseudopodium until it reaches the previously extruded mass of 

 granules at the posterior end. This stage is shown in d where 

 the internal arrow represents the direction of disintegration. 



Figures 2 and 3 illustrate the same stages in the disintegration 

 of two other individuals. Figure 4a is an amoeba with several 

 slender pseudopodia, which are numbered in the order of their 

 formation, 5 being the most recently formed, and 1 the oldest. 

 After exposure to molecular cyanide, the ectoplasm bursts in the 

 usual way at the non-active end of the animal (46) ; then disinte- 

 gration begins at the tips of the pseudopodia, first in pseudopo- 



