External: The eyelids, which have been thickening gradually, are now rapidly encroaching upon the eyes. The formation of the auricle has progressed noticeably: the tragus and antitragus especially are assuming a more definite form. The superficial vascular plexus of the head extends upward about three-quarters of the way above the eye-ear level. The hands extend further out in front of the body of the embryo, and the fingers of one hand may overlap those of the other.
Developmental Stages in Human Embryos by Ronan O'Rahilly and Fabiola Müller.
Published by Carnegie Institution of Washington, Publication 637. 1987.
Stage 22 (PDF 96 KB)
QUESTION: How far does the superficial plexus extend at this stage?