Amphibian oocytes have many copies of rRNA genes that are actively transcribed. Newt ocyte nuclei were dissected, allowed to swell in a low ionic strength high pH buffer, centrifuged through a sucrose-formaldehyde cushion onto EM grids coated with carbon films, and stained with ethanolic phosphotungstic acid producing a positive stain. In this survey image, the transcribed genes appear tree-like as the closely packed polymerases traverse the gene, and the nascent rRNA transcripts elongate until detached at the termination point.