A contribution to the embryology and phylogeny of the pycnogonids This book, "A contribution to the embryology and phylogeny of the pycnogonids", by Thomas Hunt Morgan, is a replication of a book originally published before 1890. It has been restored by human beings, page by page, so that you may enjoy it in a form as close to the original as possible. This book was created using print-on-demand technology. Thank you for supporting classic literature.