92 JOURNAL OF THE 



the use of no food other than that of other animals and 

 plants; but there is also no doubt that this is a process re- 

 quiring considerable time as compared with that which 

 occurs when they chance to meet with their own kind, 

 since in the former case the food has to be digested, while 

 in the latter it has not. It was my good fortune to find a 

 large heliazoan which had just captured an infusorium and 

 partially surrounded it. In a few minutes the infusorium 

 was completely enclosed, a clear space remaining around 

 it, however, and gradually it was moved near the center of 

 the animal, where it could be seen slowly moving its cilia 

 in the little water which immediately surrounded it and 

 which separated it from the protoplasm of the heliazoan 

 (Fig. 19, 21). Presently an amoeba came in contact with 

 the heliazoan and appeared to stick to it more or less and 

 to constantly try to move away from it. The heliazoan 

 made several efforts to surround it, but the amoeba in every 

 case moved out before being fairly imbedded, and finally, 

 after several minutes of hard struggling to ascertain which 

 was to be victorious, the amoeba escaped. It was but a short 

 time, however, before another amoeba chanced to touch 

 the heliazoan, and this time with better success to the 

 heliazoan. The amoeba, as soon as it touched the helia- 

 zoan, spread out a little on it, and at the same time the 

 protoplasm of the heliazoan began to flow around and to 

 enclose the amoeba, which now made several efforts to 

 escape, but in vain, for within a few minutes a fine film of 

 protoplasm had surrounded it, and the amoeba was within 

 the heliazoan (Fig 19). A quantity of water was also en- 

 closed with the amoeba, and in this it exhibited consider- 

 able activity, even after it had been carried nearh" to the 

 center of the heliazoan (Fig. 21). It was not long, how- 

 ever, before the amoeba had assumed a globular form and 

 become motionless. I mention this instance in which the 

 heliazoa eat other animals merely to bring out the strik- 



