88 JOURNAL OF THE 



(Fig. 5). This individual was watched until it had 

 developed three rays and several more vacuoles (Fig. 6), a 

 process requiring about twenty-five minutes, during which 

 time it had eaten nothing except one of the youngest 

 heliazoa without a vacuole. Under the one-twelfth oil 

 emersion I was able to detect the axis cylinder in two of 

 the rays, but not without sqme doubt in the third ray. 



Very near this individual (Fig. 6, 26) was another helia- 

 zoan of a much greater size (Fig. 25), and by touching the 

 cover-glass with a needle I soon brought the two so near 

 that the tip of one of the rays of the smaller heliazoan 

 touched the larger animal. Wishing to observe the result 

 of this contact I waited a few minutes, when it became 

 apparent, that the smaller individual was drawing in its 

 ray, which was in contact with the larger heliazon, and 

 was thus drawing itself towards it. The larger animal, 

 offering the greater resistance, did not appear to move. 

 Five minutes from the time the ray first touched the other 

 heliazoan the two had come in contact, whereupon a union 

 occurred and immediately the two blended into one. The 

 smaller animal appeared to flow into the larger and to dis- 

 perse itself through it in a manner which is common to 

 all these animals, young as well as full-grown, and which 

 will be described later when we reach a nearly mature 

 heliazoan. Before the union of these two animals they 

 appeared alike except in size and number of vacuoles, but 

 shortly after the union the granules in the protoplasm 

 gradually moved towards the center of the animal, where 

 they became more numerous, and instead of being evenly 

 distributed throughout the granular protoplasm now formed 

 a central, more granular portion with an outer, clearer, 

 and less granular zone. Three more rays were also 

 developed, and the animal presented the appearance shown 

 in figure 7, which, at this stage, would probably not be 

 mistaken for any other species. Hundreds of individuals 



