I quickly read through Mulberry Street a few minutes ago, and there is a depiction of a Chinese man "eating with sticks." He is wearing sandals, a straw hat, a robe, and holding chop sticks. His facial features are not exaggerated or like a caricature in any way. To me, it's clearly a mistake.
According to this article [1] you may have read the updated version.
> Seuss actually grew to become more aware of his harmful images later in his life, and to regret them, eventually revising the Mulberry Street text and illustration. "I had a gentleman with a pigtail. I colored him yellow and called him a 'Chinaman,'" Seuss said. "That's the way things were 50 years ago. In later editions, I refer to him as a 'Chinese man.' I have taken the color out of the gentleman and removed the pigtail and now he looks like an Irishman."
