BESCHREIBUNG EINES MENSCHLICHEN KEIMLINGS MIT 5 URSEGMENTPAAREN

Abstract

A human embryo with 5 pairs of somites, found in a forensic dissection, is described. The most important findings are compared with embryos of this age group. Special consideration was given to the development of the medullary plate, of the primitive heart, of the circulatory system and the large number of primitive germ cells near the allantois. The development of the primitive organs has not reached the stage of embryo Klb. of Kromer-Pfannenstiel. Embryo G. M. of the Zurich collection can be placed in age-group 10 (according to Streeter) between the numerous embryos with 4 somites and the embryo Klb. with 6 somites. Anamnestic informations to determine the term of conception are not available. Compared with other embryos, the age of development will be 21 days.