Setting aside several ingenious and far-fetched derivations that have been proposed, I think we may safely regard the word "barnacle," as applied to the cirrhopod, as a corruption of _pernacula_, the diminutive of _perna_, a bivalve mollusk, so-called from the similarity in shape of its shell to that of a ham--_pernacula_ being changed to _bernacula_. In some old Glossaries _perna_ is actually spelt _berna_. To arrive at the origin of the word "barnacle," or "bernicle," as applied to the goose, we must understand that this bird, _Anser leucopsis_, was formerly called the "brent," "brant," or "bran" goose, and was supposed to be identical with the species, _Anser torquatus_, which is now known by that name. The Scottish word for "goose" is "clake," or "clakis,"[98] and I think that the suggestion made long ago to Gesner[99] (1558), by his correspondent, Joannes Caius, is correct, that the word "barnacle" comes from "branclakis," or "barnclake," "the dark-coloured goose." [98] See the quotation from Hector Boethius, p. 101. [99] 'Historia Animalium,' lib. iii. p. 110. Professor Max Muller is of the opinion that its Latin name may have been derived from _Hibernicae_, _Hiberniculae_, _Berniculae_, as it was against the Irish bishops that Geraldus wrote, but I must say that this does not commend itself to me; for the name _Bernicula_ was not used in the early times to denote these birds. Giraldus himself described them as _Bernacae_, but they were variously known, also, as _Barliates_, _Bernestas_, _Barnetas_, _Barbates_, etc. I agree with Dr. John Hill,[100] that "the whole matter that gave origin to the story is that the 'shell-fish' (cirripedes), supposed to have this wonderful production usually adhere to old wood, and that they have a kind of fibres hanging out of them, which, in some degree, resemble feathers of some bird. From this slight origin arose the story that they contained real birds: what grew on trees people soon asserted to be the fruit of trees, and, from step to step, the story gained credit with the hearers," till, at length, Gerard had the audacity to say that he had witnessed the transformation. [100] 'History of Animals,' p. 422. 1752.