Langland’s `Corlew’: Another Look at Piers Plowman B xiv.43.
The reference to Corlew in B.14.41-46, occurring as Patience directs Will away from a literal interpretation of his situation to a more spiritual understanding, may show WL exploiting the ambiguity of the word. In Middle English it refers both to the curlew of today (Lat. numenius, renowned as a delicacy and associated with the plover, which was said to live solely on air) and to the European quail (Lat. coturnix, often translated in ME as curlew). On the basis of Exodus 16:13 and Numbers 11:31-32 coturnix served as a reminder not to worry about physical needs and as a signal of the proper attitude of the penitent soul toward the things of the world.
MAE 62 (1993): 242-58.