Arthur's Book of Alphabets, Page 19
X for Xerxes, and Uncle has said:
“I’ll tell you about him, but now go to bed.”
Y is the Yawn, given by Arthur at last;
So they put him to bed, for his bed-time was past.
Z the Zoological Gardens must be,
Which Arthur and Baby were taken to see;
And when our young friends have learned this book through,
I think they deserve to be taken there too.