Textbook of Embryology

This work has always been distinguished by its effective use of illustrations and its emphasis on histogenesis. Recent editions have added significant data from experimental embryology and a painstaking documentation. The latter means nothing to the medical student but is of value to the instructor who wishes to judge the evidence for himself.

If grows increasingly difficult to keep successive editions of a textbook up to date without inc casing its bulk and adding to the already exorbitant cost to the student. The present work illustrates various, such difficulties. Thus in the new discussion of the menstrual cycle the old homology (Aristotle, Heape, etc.) of proestrus bleeding with menstruation is retained, although this interpretation has been disproved by histologic and hormonal studies. The chapter on the age of human embryos is chaotic because of the inadequacy of our present knowledge as to the time of ovulation, its relation to conception