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
What Bird is That? to the League for £300. The book was extolled fulsomely by S.R. Thomas, of the NSW Department of Education, as follows; ""What Bird is That?" is the most comprehensive and informative bird book published in the Commonwealth – if not in the world. The coloured plates are a triumph not only of the genius and imagination of the artist – our own Neville Cayley on whom has fallen so fittingly the mantle of his famous father – but also of the block-maker’s and printer’s art. The publishers have done nothing finer of its kind. The life-like portrayals of our feathered