Textbook of normal histology: including an account of the development of the tissues and of the organs . Transverse section of nine-day rabbit embryo, show-ing formation of primitive gut (g) by approximation ofventral plates composed of visceral layers of mesodermand entoderm (e) ; m, m, body-cavity bounded byparietal and visceral sheets of mesoderm ; n, neuralcanal. 188 NORMAL HISTOLOGY. Fig. its walls also become augmented by many new elements, the meso-dermic cells differentiating into a narrow looser zone next the ento-derm, which later becomes the submu-cosa, and a broader, more compactst
Textbook of normal histology: including an account of the development of the tissues and of the organs . Transverse section of nine-day rabbit embryo, show-ing formation of primitive gut (g) by approximation ofventral plates composed of visceral layers of mesodermand entoderm (e) ; m, m, body-cavity bounded byparietal and visceral sheets of mesoderm ; n, neuralcanal. 188 NORMAL HISTOLOGY. Fig. its walls also become augmented by many new elements, the meso-dermic cells differentiating into a narrow looser zone next the ento-derm, which later becomes the submu-cosa, and a broader, more compactstratum, representing the future mus-cular tunic. The entodermic cells, atfirst arranged as a single layer, soonundergo local proliferation, the resultinggroups of cells disposing themselves asminute cylindrical masses, which arethe earliest traces of the peptic increase in length and later en-croach upon the underlying the young gland six to eight tubulardivisions communicate with a singleduct, but as development advances theducts divide, with a corresponding dimi-nution in the number of terminal com-partments connected with each. Thepyloric glands appear about the sametime as do the peptic, or at about thetenth week of foetal life, the cells ac-quiring their characteristic form andappearance during the later stages. Atfirst and during a considerable periodthe c
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Keywords: ., bookauthorpiersolgeorgeageorgea, bookcentury1800, bookdecade1890
