An introduction to the study of embryology / by Alfred C. Haddon.

  • Haddon, Alfred C. (Alfred Cort), 1855-1940.
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: An introduction to the study of embryology / by Alfred C. Haddon. Source: Wellcome Collection.

Provider: This material has been provided by University of Bristol Library. The original may be consulted at University of Bristol Library.

    122/374 (page 88)
    Fjo. 79.—Five Diagrammatic Figures Illustrating the Formation of thk F<etal Membranes of a Mammal. [Frmn KoUiker.] In I, 2, 3, 4, the embrj'O is represented in longitudinal section. 1. Oosperm with zona pellucida, blastodermic vesicle, and embryonic area. a. Oosperm with commencing formation of umbilical vesicle and amnion. 3. Oosperm with amnion about to close and commencing aUantois. 4. Oosperm with villous siibzonal membrane, larger aUantois, and mouth and anus. 5. Oosperm in which the vascular mesoblast of the aUantois has extended round the inner surface of the subzonal membrane, and united with it to form the chorion ; the cavity of the aUantois is aborted. The yolk-sac (umbilical vesicle) has greatly diminished. The large amniotic cavity surrounds the umbilical cord. This fig. represents an early human ovum. a. epiblast of embryo; a', epiblast of non-embryonic part of the blastodermic vesicle ; ah. cavity of the amnion ; al. allaiitois ; am. amnion; cw. amniotic uheatli round tlie umbilical cord ; ch. chorion; ch.z. villi of chorion; d. zona pellucida (radiata) ; d'. processes of zona; dd. embryonic hypoblast; df. area vasculosa; dg. stalk of yolk-sac; ds. yolk-sac (umbilical vesicle); e. embryo ; hh. pericardial cavity ; i. non-embryonic hypoblast; kh. cavity of the blastodermic vesicle, which practically Is equivalent to the yolk-sac ; ks. head-fold of amnion ; TO. embryonic, m' non-embryonic, mesoblast; r. space between chorion and amnion containing albuminous fluid ; sh, subzonal (serous) membrane; st. sinus terrainalis ; sz. subzonal villi ; vt. ventral body-wall in tlie region of the heart.