Y is the third and final letter that has been excluded from the Motif Index. Once more, I searched for words that start with Y, and someone on Twitter suggested Yellow. I was not disappointed.
A2391.1 Why canary's eggs are yellow
First off: This is another one of Thompson's misnomers. The story actually explains why canary's feathers are yellow. It is a Flemish legend.
|This one looks a little hung over|
According to the story, canaries used to be white. One day, however, they went out to celebrate on a feast day, and got a little too much to drink. Instead of sitting on their eggs, they were out late into the night. When they returned home, the male canary fell into the nest and broke the eggs; his feathers were stained golden yellow from them. The female fell in too, but since the male had already soaked up most of the yolk, she did not get the same bright color.
I feel like this story was supposed to teach us something.
(Story in German here.)