Lapwing Vanellus vanellus, Vanneau huppé.
MM 1 4 32 With maids to seem the lapwing, and to jest
ERR 4 2 27 Far from her nest the lapwing cries away;
ADO 3 1 24 For look where Beatrice like a lapwing runs
HAM 5 2 183 p This lapwing runs away with the shell on his head.
The Lapwing is still common even if it has long been hunted for food and had its eggs collected for the same purpose. It is the typical wader of farmlands and coastal pastures.
All four occurrences are based on two proverbial sayings recorded by TILLEY (L68 and L69):
1. L68 "The Lapwing cries most when farthest from her nest" expresses insincerity, it is based on the way the lapwing tries to distract the predator's attention from its nest.
With maids to seem the lapwing, and to jest
Tongue far from heart
(MM 1 4 32-3)
Far from her nest the lapwing cries away;
My heart prays for him, though my tongue do curse.
(ERR 4 2 27-8)
In the two passages quoted above, the same elements are found together to express insincerity; the lapwing and an opposition between the heart and the tongue; a simile drawn from the natural world combined with two metonymies. About the bird itself Chaucer had already mentioned: "The false lapwynge , ful of trecherye" in The Parlement of Foulys, l 347.
2. L69 "Like a Lapwing that runs away with the shell on its head" refers to the behaviour of the young of some ground-nesting species, they are able to leave the nest almost as soon as having hatched in case of an incoming danger:
This lapwing runs away with the shell on his head.
(HAM 5 2 183 p)