I’m not much of a linguist, but when I travel I love to learn odd expressions from local languages and cultures. British illustrator Paul Blow has been creating wonderful images based on idioms that has discovered during his own travels. While many of these sayings are not readily translatable into English, Blow captures the universal humor in them all.
all images ©Paul Blow
Travel Between The Pages 
Wonderful!
Hello, your title is not a right translation . “Quand les poules auront des dents” is the phrase, and “une poule” is a hen, not a chicken . Then the curious absence of the future tense after when in English brings a risk of confusion, for the reader cannot guess this phrase is originally about future . “When hens will have teeth” is an exact though improper translation .