Endodermic evagination

Endodermic evagination relates to the inner germ layers of cells of the very early embryo, from which is formed the lining of the digestive tract, of other internal organs, and of certain glands, implies the extension of a layer of body tissue to form a pouch, or the turning inside out (protrusion) of some body part or organ from its basic position, for example the para-nasal sinuses are believed to be formed in the fetus by 'ballooning' of the developing nasal canal, and the prostate or Skene's gland formed out of evangations the urethra. ^[1][2][3]

References

1. Shipley, A.E. (1911). The Shipley collection of scientific papers. The Shipley collection of scientific papers. Retrieved 4 April 2015.
2. Esterly, C.O. (1907). Some observations on the nervous system of Copepoda. University of California publications in zoology. The University press. Retrieved 4 April 2015.
3. Rodeck, C.H.; Whittle, M.J. (2009). Fetal Medicine: Basic Science and Clinical Practice. Churchill Livingstone. ISBN 978-0-443-10408-4. Retrieved 4 April 2015.