Fig. 1.

Human embryo at Carnegie Stage 23, the end of the embryonic period (GW8). It is 30 mm long. Image from the Kyoto Collection reproduced with permission of Prof Kohei Shiota, Graduate School of Medicine, Kyoto University, and obtained with permission of Dr. Mark Hill, University of New South Wales, http://embryology.med.unsw.edu.au/embryo.htm