Feather development non-nervous. They have a tubular central shaft called the rachis; coming off either side of the rachis are the veins, which have a series of barbs with interlocking connections that are called barbules. The rachis and attached veins make up the spathe. The opposite of the rachis is the calamus, which anchors the feather to the body and is moved by attached dermal muscles. There are many different types of feathers that mostly follow this basic design with few variations based on evolutionary needs. Feathers are sometimes referred to as “elaborate reptile scales” just as birds are sometimes viewed as
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