The diseases of the foetus in utero : not including malformations; with an outline of foetal development.

  • Madge, Henry.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: The diseases of the foetus in utero : not including malformations; with an outline of foetal development. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    next ciianges wliicli occur are the divergence and approximation of the two parallel cords near to one extremity, so as to include between them three unoccupied spaces. The first corresponds to the future position of the olfactory ganglia; second, the optic; third, the medulla oblongata. On the second or third day, two small capsules are deve- loped from the sides of the medulla oblongata at its upper part; these are the rudiments of the organ of hearing. Another pair of vesicles are soon after produced from the sides of the middle ganglia, which soon indicate, by the collection of pigment which ensues, the formation of eyes; and a third pair from the anterior ganglia become developed into the nasal fossse. Near the posterior part of the primitive trace a space exists, which remains permanently in birds under the name of sinus rhomboidalis; this point corresponds with the numerous nerves which are intended to supply the lower extremities.'' In another place the same observer remarks, In tracing the modifications which the mucous layer of the germinal membrane undergoes, it will first be seen that immediately after the appearance of the primitive cumuli the mucous layer dips down at each side, and forms two parallel longitudinal folds, including between them a groove. The colour of the yolk in contact with this mem])rane becomes of a lighter colour, and more fluid; the groove then progresses into