Excerpt from Quarterly Journal of Microscopical Science, 1892, Vol. 33I have not deemed it necessary to give references for facts to be found in every text-book, though I have verified as far as possible every statement from the original authorities. In all other cases I have cited my authority in a foot-note.The following is a list of the text-books and papers of general interest to which I may refer the reader.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.