St. Catherine of Alexandria
Manuscript illumination from the Gualenghi d'Este Hours
As an emblem of her erudition, the saint is shown reading a book. In the niche above the book is a statue of the Virgin and Child, who figure in later versions of the Catherine story. At her left is her most common attribute, a spiked wheel. Uncommonly, she does not wear a crown.
The images in the margin may or may not relate to the portrait of the saint. In the left margin the pelican piercing its breast is a well-known symbol of Christ, although usually it is pictured with the chicks that are fed by its blood. The dragon may refer to the slogan of the House of Este, ab insomni non custodita dracone, "not retained by the sleeping dragon."
In the right margin a hand holds on to an anchor, recalling the reference in Hebrews 6:18-19 to "the hope set before us. Which we have as an anchor of the soul, sure and firm…." Possibly the four points of the anchor refer to the four evangelists. In Hebrews the "two immutable things" on which hope relies are God's promise and his oath. In this image, however, the two immutables are the bread and wine of the Eucharist, which are represented by the sheaves and the flowing blue flourish.
Read more about images of St. Catherine of Alexandria.
Read more about the anchor symbol.
Source: this page at Wikimedia Commons.