Butterfly 2 by Albert Bierstadt - c.1890

Butterfly 1 by Albert Bierstadt - c.1890

Butterfly 6 by Albert Bierstadt - July 1898

Butterfly 5 by Albert Bierstadt - 1898

Butterfly 4 by Albert Bierstadt - c.1895

Butterfly 8 by Albert Bierstadt - July 1890

Butterfly 7 by Albert Bierstadt - 1896

Mackerel Sky by Eric Ravilious, 1938

V for Valentine from the Erotic Alphabet by Joseph Apoux - 1880 - Square Greeting Card

When Hearts Are Trumps, Art Nouveau Poster by Will Bradley, 1894 - Square Greeting Card

Tiger Love, 1924 - Greeting Card

Title Page from the Portfolio Love (Amour) by Maurice Denis, 1899 - Greeting Card

Venus and Love (detail) by Jacob de Gheyn (II), 1605 - 1610 - Greeting Card

Passion by Floris Arntzenius (1864-1925) - c.1893 - Greeting Card

Love Flight of a Pink Candy Heart by Florine Stettheimer, 1930 - Greeting Card

Interior with Couple and Screen (Intimacy) by Felix Vallotton, 1898 - Greeting Card

Johann Bayer's Zodiac, 1603 - Postcard Collection

Sagittarius by Johann Bayer, Augsburg, Germany, 1603 - Postcard

Libra by Johann Bayer, Augsburg, Germany, 1603 - Postcard

Pisces by Johann Bayer ' Augsburg, Germany, 1603 - Postcard

Leo by Johann Bayer, Augsburg, Germany, 1603 - Postcard

Aquarius by Johann Bayer, Augsburg, Germany, 1603 - Postcard

Gemini by Johann Bayer, Augsburg, Germany, 1603 - Postcard