Publisher's Synopsis
Excerpt from An Essay on the Development of the Mouth Parts of Certain Insects
Forming the lower lip and closing the mouth inferiorly is the labium, also made up of a number of sclerites and usually furnished with palpi. It is never entirely paired in existing insects, but is assumed to be made up of two more or less united structures, similar in essential character to the maxilla, as has been well stated by Prof. J. H. Comstock. This labium is an exceedingly important structure and forms the oral termination of the digestive tract or the mouth of the oesophagus. Attached to the inner Surface of the labium is the hypopharynx, a variably devel oped structure, which is supposed to be the remnant of another originally paired organ, the endo-labium. I have never seen the genera in which it is said to be well devel oped, hence have no well-founded opinion to ofier. I find it uniformly a Single organ, often highly developed and gustatory in function, sometimes a merely passive structure more or less closely attached to the ligula, usually very near the Opening into the digestive tract. 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.