Hertwig, Oskar

This volume contains three chapters that are written by different authors. These chapters are about the development of the outer body forms of vertebrates, the development of the Eggshell membrane of reptiles and birds as well as the shell membrane of mammals and something about the placenta.

According to the preface to this volume, there are probably as many views about the initial formation of the vessels and blood as researchers have expressed themselves on this subject, which in any case proves that this is one of the most difficult matters. Thus, after looking at the literature, the authors needed their own investigations.

The main task of the handbook is to give an exhaustive overview of the entire field of comparative development based on sources. The results of the experimental development theory are also presented. Contains articles of different authors.