Excerpt from The American Journal of Anatomy, 1912, Vol. 12 Born's article reviews the earlier development of the cloa eal region in a very complete manner, and the substance is as follows: The entoderm of the enteron comes into direct relation with the surface ectoderm in the pharyngeal and cloacal membranes during the formation of the head and tail folds. Both of these membranes lose their primitive position and become folded into the substance of the embryo through increase in the surrounding mesoderm. The allantois, which is developed dorsally in the mammalian embryo (human and guinea pig excepted), shifts to a ventral position on the gut, and is gradually displaced from its intimate relation to the yolk sac through increase in the amount of mesodermal tissue. The primitive streak is carried to the ven tral surface of the body during the formation of the tail fold, and forms the whole or part of the cloacal membrane. Kolliker Strahl and Bonnet believe that the caudal end of the primitive streak is made up of applied layers of ecto and entoderm, and that it enters as such into the formation of the cloacal membrane. Keibel argues that this primitive rela tion of the ecto and entoderm is lost through interposition of mesoderm; the latter disappearing later with restoration of the original two layered condition. 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.

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Excerpt from The American Journal of Anatomy, 1914, Vol. 16 This is the third of a series of papers concerning the develop ment of the mucous membrane of the digestive tract. The first two (johnson '10 and '13) deal with the oesophagus, stomach, and small and large intestines. In this paper an account of the development of the rectum is given, particular attention being paid to the formation of the pars analis recti. 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.

Excerpt from The American Journal of Anatomy, 1915, Vol. 17 I have prepared the following summary so that what we know Of the comparative distribution: Of mitochondria in vertebrate nerve cells may be seen at a glance. In it, the forms 111 which mitochondria are described by me for the first time, are given in italics, the others being recorded in plain type. 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.

Excerpt from The American Journal of Anatomy, 1916, Vol. 19 I am indebted to Prof. R. E. Sheldon for kind encouragement and valuable criticism in connection with the work of this paper. In making the figures I have received a number Of helpful sug gestions from Miss S. E. Watson, artist Of the Department of Anatomy. 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.

Excerpt from The American Journal of Anatomy, Vol. 23: 1918 A careful examination of the ovary Of a bird which has been actively laying shows three kinds of structures: the yolks of various sizes indicating different stages of development, the discharged follicles in various stages of regression, and the atretic follicles or degenerating eggs of different sizes. These are all easy to identify when they are large enough to protrude far from the surface of the ovary, that is, when they are larger than 2 or 3 mm. In diameter. Under this size, it is impossible to distinguish the discharged follicle from the atretic. Both of them show a yellow or orange spot in the center. The ques tion naturally arises whether these yellow spots are homologous in structure and origin with the mammalian corpus luteum. They never develop into a large mass like the corpus luteum of the mammal. They have the color of the spots on the cow ovary which indicate remains of old corpora lutea. In order to interpret these yellow spots, a study has been undertaken of the progressive and regressive changes in the cell structure of egg follicles in different conditions, undischarged, discharged and atretic. 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.

Excerpt from The American Journal of Anatomy, 1917, Vol. 21 The difference in size in the two figures is, I believe, without special signifi cance. Figure 1 is from a safranin-lichtgrun preparation and figure 2 from an iron-alum-haematoxylin slide. The latter is reconstructed from two adjacent sections. 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.