Feather development grows, its spathe, which is where the rachis and vanes attach, continues to form. When spathe is finished developing, the calamus begins to form within the base of the spathe. The calamus is the quill of the feather, which is the bottom portion that stays mainly within the pulp cavity. From there, the feather is fully developed and will remain as such until molting occurs, causing it to fall off. Feathers fall off during molting, which occurs in the at different times through the year depending on the type of bird. Birds can molt for seasonal, reproductive and many other
The Bird in a Cage The Bird in a Cage The Bird in a Cage, or The Beauties is a Caroline era comedy written by James Shirley, first published in 1633. The play is notable, even among Shirley's plays, for its lushness — what one critic has called "gay romanticism run mad." The play was licensed for performance, under the title "The Beauties," by Sir Henry Herbert, the Master of the Revels, on 21 January 1633. It was published in quarto in the same year, printed by B. Alsop and T. Fawcet for the bookseller William Cooke. The title page of the 1633 quarto states