J a 



I' 



Figure 1. Photomicrographs of I-cells and R-cells. a. The cells had adhered to a glass 

 surface under a layer of salt solution, c. The cells were pressed between a cover slip and 

 agar. Note that the I-cell has engulfed one of its neighbors, b, d, and e. The cells had 

 adhered to an agar substratum. 



