Histological observations of human embryos hitherto have been carried out using paraffin sections of 5 to 10 m thickness, stained with the H-E method or simply with carmine. Because of the thickness, cells are arranged in 2 or 3 layers in one section and the histological details are not always clear. This book provides detailed morphological features of a very well preserved human embryo with fifteen somites. The sections are about 0.75 m thick and stained with toluidine blue. The thinness of sections and clearness of staining reveal the histological details of this embryo very accurately. A...