Excerpt from The Pygidiidae, a Family of South American Catfishes Head flat rounded, eyes small, superior, covered by the skin. Head times in length to basis of caudal fin. Depth at D. I. One-half length to basis pectoral fin; width of head two-thirds the same dis tance. Inter-orbital width times in length of head. Maxillary and external mental barbels extending beyond basis of pectoral; inner mental barbel one-half the same. Radii D. 7; P. 8; V. 6; A. 11; caudal acuminate. Skin entirely smooth. 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.