Bulletin Of The United States Bureau Of Fisheries Vol 38

Author : Henry O'Malley
Publisher : Forgotten Books
ISBN 13 : 9780428554569
Total Pages : 422 pages
Book Rating : 4.5/5 (545 download)

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Download or read book Bulletin of the United States Bureau of Fisheries, Vol. 38 written by Henry O'Malley and published by Forgotten Books. This book was released on 2018-01-08 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Bulletin of the United States Bureau of Fisheries, Vol. 38: 1921-1922 There are few animals that lend themselves more readily to a laboratory or lecture demonstration than do these stem - dwelling larva. They seem to differ decidedly from other chironomids, especially those that characteristically live in a mud burrow, in their reactions to strong light. Their greater tolerance of light enables one to demon strate the Silk-spinning movements and the general behavior of the larva by means of a stereopticon. The only requirements are that the larva shall have recently built a fresh, clean Silk tube in a glass preparation, and that the temperature of the water be kept down to normal room temperature. The reason for requiring that the silken tube be a fresh one is that after a week or two the silk becomes much discolored by the lodgment of fine particles as well as by the deliberate attachment of masses of castings to the ends of the burrow. It is only necessary to remove the larva by a jet Of water and then the tube can be removed by a needle. A few hours will usually suffice to enable them to again replace the silken tube. The temperature is easily controlled by having a Specially constructed lantern slide through which a current of water can be made to pass. A type used with considerable success was constructed as follows. 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.