A frame from the grouped movie of a Balamuthia mandrillaris ameba within a culture of monkey kidney cells. Accompanying photographs are enlargements of the tips of pseudopodia to demonstrate their flexibility and movement, and a second set of photographs demonstrate the puncture of the plasma membrane of a monkey kidney cell. The first shows an indentation in the cell membrane, the withdrawal of the pseudopodia tip and the subsequent rupture of the membrane in the area indented by the amebic tip. The eventual break in the membrane may have resulted from the release of a proteolytic enzyme. Details of the preparation can be found in CIL:19325.