Excerpt from Contributions to Embryology, Vol. 6: Nos. 15, 16, 17, 18, 19 In a number of his experiments Lewis found that the material withdrawn with the needle-point came from one Side of the anterior end of the embryonic shield, with a resulting abnormality Of the eye on that side. In a specific case, at. The time of hatching, the right eye of the specimen consisted of a small bit of retina connecting with the otherwise almost normal brain-wall. The left eye was apparently normal, as were also the brain and the nasal pit. In other specimens, in which the operation was about medial and was done at the time the embryonic shield was beginning to form, the embryos developed with the two eyes in contact, with two optic nerves and two lenses. Among other specimens there is one with a cyclopean eye, having a layer of pigment narrowing between the two eyeballs. In specimens operated upon at a little later stage there is a median cyclopean eye with two lenses, one pupil, and one cup cavity. Using Lewis's language, the large Optic cup shows in sections a very beautiful median eye with complete con tinuity of the layers of the retina of two components about a single large cup cavity of a Single lens. 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.