Publisher's Synopsis
Excerpt from University of California Publications, Vol. 1: Zoology; With 28 Plates
If there is one thing more than another which the preparation of this paper has brought emphatically to my attention, it is the great necessity for long-continued observations on the growth and development of hydroids under natural and artificial condi tions. Unfortunately the systematist is forced to rely for his determinations almost exclusively upon skeletal characters, which are peculiarly variable. Size, habit, branching, length of branches and internodes, thickness of perisarc, shape and ornamentation of hydrothecae, kind and amount of annu lation, number of tentacles on the hydranth and on the medusa at the time of liberation - all these are subject to often perplexing variations. This leaves little doubt that when proper measures are taken for the observation of living animals the number of species will be materiallv decreased. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This 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.
