Lichen by Ernst Haeckel - 1904

Batrachia by Ernst Haeckel - 1904

Mycetozoa, from Ernst Haeckel's Kunstformen der Natur - 1904

The Vine Root Cut Transversally by Nehemiah Grew - 1682

Sour Orange, Terrestrial Mollusk, and Larkspur

Love-in-a-Mist, Sweet Cherry, and Spanish Chestnut

Nepenthaceae

Window Looking Out On the Park by Caspar David Friedrich - c. 1810

Frustules of Diatoms by Julius Weisner - 1870

Die Pflanzenwelt by Otto Warburg - c. 1920

Dew on a Blade of Grass by Wilson Bentley - c. 1900