Excerpt from Ophiura BrevispinaDorsal - aboral - above - over. Ventral - oral - below - under. Anterior - forward - before. Posterior - backward - behind.In the drawings of the larvae, when the ventral side is up and the anterior end is nearest the top of the page, then the reader's left is also left in the ngure.For convenience in description. The various stages taken to illustrate the life history of the species have been designated by letters of the alphabet, this method seeming preferable to one in which age is used as a distinguishing character, since the progress of development at any age depends so intimately on the varying conditions of environment.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.