oldTor:
Diatoms. Monochrome. 119:1
oldTor:
Living diatoms. Collage. Positive phase contrast
oldTor:
Diatoms under a microscope. Positive phase contrast. 123:1
oldTor:
Diatom algae. Phase contrast, monochrome.
oldTor:
Live diatom. Monochrome, inversion.