"There are also the _cleek geese_. The shells in which this fowl is
said to be produced, are found in several isles sticking to trees
by the bill; of this kind I have seen many,--the fowl was covered
by a shell, and the head stuck to the tree by the bill,--but never
saw any of them with life in them upon the tree; but the natives
told me that they had observed them to move with the heat of the
sun."--See also Gratianus, Lucius, Ware's _Antiquities_, &c.
Eating sea-birds on fast days is a very ancient custom. Socrates
mentions it in the 5th century: "Some along with fish eat also birds,
saying, that according to Moses, birds like fish were created out of the
waters." Mention is made in Martin's _Western Isles_, of a similar
reason for eating _seals_ in Lent. _Cormorants_, "as feeding only on
fish," were allowable food on fast days, as also were _otters_.