I went book hunting this morning - and came back with some amazing finds. This illustration is from a small paperback by Gerald Rose, titled 'How St. Francis tamed the Wolf". Published in 1967.
Gerald Rose is a great illustrator, and I wish I had kept all the books by him that I sold.
I love the freedom of his line, and his characters, and colours...
You can find more illustrations by Gerald Rose in my Flickr collection of vintage children's books, link on the left.