Gerald of Wales:
Barnacle Geese should convince the Jew of the Immaculate Conception

There are here many birds that are called “Barnacles” [barnacoe] which in a wonderful way Nature unnaturally produces; they are like wild geese but smaller. For they are born at first like pieces of gum on logs of timber washed by the waves. Then enclosed in shells of a free form they hang by their beaks as if from the moss clinging to the wood and so at length in process of time obtaining a sure covering of feathers, they either dive off into the waters or fly away into free air. . . I have myself seen many times with my own eyes more than a thousand minute corpuscles of this kind of bird hanging to one log on the shore of the sea, enclosed in shells and already formed. . . . Wherefore in certain parts of Ireland bishops and religious men in times of fast are used to eat these birds as not flesh nor being born of the flesh. . .

Be wise at length, wretched Jew, be wise even though late. The first Generation of man from dust without male or female [Adam] and the second from the male without the female [Eve] thou darest not deny in veneration of thy law. The third alone from male and female, because it is usual, thou approvest and affirmest with thy hard beard. But the fourth, in which alone is salvation, from female without male, that with obstinate malice thou detestest to thy own destruction.

Blush, wretch, blush, and at least turn to nature, She is an argument for the faith and for our conviction procreates and produces every day animals without either male or female.