This video is composed of a sequence of time lapse films created by John Tyler Bonner in the 1940s to show the life cycle of the cellular slime mold, Dictyostelium discoideum. As only the second person to study slime molds, Bonner frequently encountered audiences who had never heard of, let alone seen, the unusual organism. He therefore decided to create a film to present at seminars in order to introduce his object of study. Bonner created the video for his senior thesis at Harvard University with the help of photographer Frank Smith. Bonner began to work at Princeton University in 1947, thus the mention of that university on the title screen of the film. It was digitized and narrated by developmental biologist Rachel Fink of Mount Holyoke College. Includes (approximate starting times given): Amoebae [00:02]; Aggregation [00:27]; Migrating Pseudoplasmodia [02:16]; Culmination [03:28]; Trisected Pseudoplasmodium [04:17].