C.B. Falls/ published 1923 by Books of Wonder
I got this book as a freebie while I was working in New York over 15 years ago and held onto it for my future kid. It was one of the earliest books I read to him, and I really just love it. An alphabet book for the design-conscious, the wood cuts are stunning. C.B. had a style that was copied by many, and still is today because his pictures are so much fun to look at and get lost in. Each letter of the alphabet is given a corresponding animal...
X is for Xiphius
Y is for Yak
Z is for Zebra
...though the antelope looks a lot like a goat to me. You can actually buy prints and see all the illustrations from the book here.