I recently found a 1961 printing of The True Book of Time, written by Feenie Ziner and Elizabeth Thompson, illustrated by Katherine Evans. I’ve been unable to find out anything online about Katherine other than a brief bio at the Washington Island Art and Nature Center:
Katherine Floyd Evans, born in Sedalia, MO in 1899, was multi-talented, fearless yet ladylike, whimsical, and a keenly intelligent artist who came to the Island with her family for the summers in the early 1900s.
She studied in Paris at the Ecole des Beaux Arts, in the Art Colony in Provincetown, and at the Chicago Art Institute.
She was always an artist . . . drawing, painting, sculpting . . . but when her husband died she made a living for herself and her two children as a children’s book writer and illustrator. Traveling the world for up close and personal views of Mexicans, Ethiopians, Parisians, West Africans, and others, she illustrated more than 75 books for children and used many of those experiences to inspire her paintings and her life.
Katherine Evans is probably best known for her illustrations for The Littlest Angel, a book I had as a small child. I remember not liking the story but loving the pictures. Here are a few from The True Book of Time:
LibraryThing.com seems to have a complete list of books illustrated by Katherine Evans, most of which are out of print.