Infusoria in een druppel water, houtgravure, gepubliceerd in 1893 - Stockillustratie

Microscopic illustration of infusoria in a drop of water. Infusoria is a collective term for minute aquatic creatures such as ciliates, euglenoids, protozoa, unicellular algae and small invertebrates that exist in freshwater ponds. Wood engraving, published in 1893.