Drops of food coloring move through water very quickly, never staying in the same place or same shape for very long. The images on this page are examples of the surrealist technique, coulage, or more precisely, "transient coullage," in that their shapes are ephemeral, persisting only long enough for the camera to capture them as they diffuse through water.
Also, these pictures are described as "asymmetrical" because they have not been doubled or folded along an axis, unlike the symmetrical collection.