Crefydd iâr wrth ei gylfin – you can tell what the hen’s thinking by looking at her beak.

Crefydd iâr wrth ei gylfin.
Dihareb Cymraeg. Ystyr Saesneg; English meaning:
The hen’s beak her mind doth speak. (i.e. the face without shows what is within).

Addaswyd o ddetholiad Diarhebion Cymraeg gan J. J. Evans 1965.