Thus we see that in early and even later days a good deal hung on the truth of this story of the generation of barnacle geese. The story was popularly discussed by the devout and by sceptics, and appears to have been known in France as "l'histoire du canard." At last in the seventeenth century it was finally discredited, owing to the account given by some Dutch explorers of the eggs and young of the barnacle goose--like those of any other goose--and its breeding-place in the far north on the coast of Greenland. The discredited and hoary legend now became the type and exemplar of a marvellous story which is destitute of foundation, and so the term "un canard" (short for histoire d'un canard), commonly applied in French to such stories, receives its explanation. Our own term for such stories, in use as long since as 1640, namely, "a cock-and-bull story," has not been traced to its historical source.[3]
[3] Probably it means "a silly story told by a cock to a bull!" as suggested by the French word _coq-à-l'âne_, which means a story told or fit to be told by a cock to an ass!
That the story of the goose or duck and the transformed barnacle was a popular one in Shakespear's time, whether believed or disbelieved, appears from his reference to barnacles in "The Tempest." Caliban says to Stephano and Trinculo, when they have all three been plagued by Prospero's magic, and plunged by Ariel into "the filthy mantled pool" near at hand, "dancing up to their chins": "We shall lose our time and all be turned to barnacles, or to apes with foreheads villainous low." Probably enough, this is an allusion to the supposed Protean nature of barnacles. They are not alluded to elsewhere in Shakespear.
One of the most precise accounts of the generation of geese by barnacles is that of the mediaeval historian Giraldus Cambrensis, who visited Ireland and wrote an account of what he saw in the time of Henry II, at the end of the twelfth century. He says: "There are in this place many birds which are called Bernacæ; Nature produces them, against Nature, in a most extraordinary way. They are like marsh-geese, but somewhat smaller. They are produced from fir timber tossed along the sea, and are at first like gum. Afterwards they hang down by their beaks as if they were a seaweed attached to the timber, and are surrounded by shells in order to grow more freely. Having thus in process of time been clothed with a strong coat of feathers, they either fall into the water or fly freely away into the air." "I have frequently seen," he proceeds, "with my own eyes, more than a thousand of these small bodies of birds, hanging down on the seashore from a piece of timber, enclosed in their shells and ready formed. They do not breed and lay eggs like other birds; nor do they ever hatch any eggs nor build nests anywhere. Hence bishops and clergymen in some parts of Ireland do not scruple to dine off these birds at the time of fasting, because they are not flesh nor born of flesh!"