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
A Summer Bird-Cage A Summer Bird-Cage A Summer Bird-Cage is the 1963 debut novel by Margaret Drabble published by Weidenfeld & Nicolson. The title of the novel is taken from a quotation from the play "The White Devil" by John Webster: ‘"Tis just like a summer bird-cage in a garden: the birds that are without despair to get in, and the birds within despair and are in a consumption for fear they shall never get out." The novel centres on two characters who are sisters, Sarah and Louise. At the beginning of the story Sarah (who has recently graduated from Oxford University) has