492 J. A. DAWSON 



for 5 hours. At the end of 7 hours they could no longer be 

 seen. This animal was kept for 11 hours and 40 minutes, when 

 fission took place. 6pa (75 x 30 m) was fixed and stained and 

 was normal in cytological structure (fig. 10). 6pp was stained 

 at the end of llj hours and examination showed that complete 

 digestion of all the ingested animals had taken place. The size 

 of this animal, 84 x 36 n, was practically the same as that of 

 the average noncannibalistic animal. 



No. 7. In 2| hours the contained bodies could still be distinctly 

 seen. In 2 hours and 57 minutes fission had taken place. 7a, 

 with one body, was kept for 9 hours, at which time the body was 

 still visible. The preparation showed plainly the nuclear struc- 

 ture of the swallowed animal. Size, 93 x 45 /z. 7p showed the 

 presence of the three bodies for 9 hours, when they could no 

 longer be seen. The animal was kept for 11 hours, at the end of 

 which it seemed, except for its slightly greater size (90 x 56 m), 

 like a typical specimen. The stained preparation made at this 

 time is shown in figure 12. Here the only indication of the 

 ingested animal is the presence of two faintly stained chromatin 

 bodies to the left of the posterior macronucleus of the cannibal. 

 (The specimen is mounted ventral surface up.) 



No. 8. At the end of 2 hours only two bodies could be seen 

 distinctly. These gradually disappeared until little sign of any 

 bodies could be seen at the end of 6 hours. In 7 hours fission 

 occurred. 8a was stained and showed details of normal structure. 

 Size, 75 X 42 ix. 8p was stained at the end of 14 hours and 

 showed the presence of a vacuole staining faintly and contain- 

 ing no chromatin. Size, 95 x 45 /x (fig. 17). 



Cannibals with five bodies. No. 9. Little change could be 

 observed at the end of 1 hour and 20 minutes. In 2| hours 

 only three bodies could be distinctly seen. In 3 hours one body 

 remained visible. The stained specimen showed that this body 

 still preserved its nuclear structure, while remains of two of the 

 other bodies were present as fairly large faintly staining vacuoles 

 containing no chromatin. Size, 108 x 51 /x. 



No. 10. Bodies remained distinctly visible with little change 

 for 3 hours. These gradually became less distinct until, at the 



