File:Bryce1908 fig06.jpg

Figure 6. Hypothetical stage of the human

T. H. Bryce from "Quain's Anatomy", 11th Ed.

This diagram was designed to show, in one figure, the probable early condition of the trophoblast, and an early phase of the of the cavity of the blastocyst relatively to the size of the amnio-embryonic and entodermic vesicles, ia probably rendered too small. We do not know how soon the trophoblast shell begins to assume the dimensions so much out of proportion, as they appear in our ovum and in Peter's. The trophoblast is shown with a cellular and a plasmodial layer, but it is probable that when the plasmodium is at the stage represented, the embryonic rudlment is not so far differentiated as it appears in the diagram. With these qualifications the figure, which was printed before the present ovum was obtained, is probably not essentially incorrect.

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