Excerpt from Manual of Conchology, Vol. 25: Gastrocoptinae, Vertigininae In Vertigo, the point of the outer lip, running forward or bent inward, has been termed the auricle by Dr. Sterki. The ridge encircling the whorl behind and parallel to the free margins of the peristome is known as the crest (collar. 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.