. The elements of Embryology,. . A. Head of an Embeto Chick of the Fourth Day viewed from below AS AN opaque object. (Chioiuic acid preparation.) CH. cerebral hemispheres. FB. vesicle of the third ventricle. Op. eyeball. nf. naso-frontal process. M. cavity of mouth. S. M. superior maxillary process of i^. i, the first visceral fold (inferior maxillary process). F. 2, F. 3, second and third visceral folds. N. nasal pit. In order to gain the view here given the neck wai cut across between the third and fourth visceral folds. In the section e thus made, are seen the alimentary canal al with
. The elements of Embryology,. . A. Head of an Embeto Chick of the Fourth Day viewed from below AS AN opaque object. (Chioiuic acid preparation.) CH. cerebral hemispheres. FB. vesicle of the third ventricle. Op. eyeball. nf. naso-frontal process. M. cavity of mouth. S. M. superior maxillary process of i^. i, the first visceral fold (inferior maxillary process). F. 2, F. 3, second and third visceral folds. N. nasal pit. In order to gain the view here given the neck wai cut across between the third and fourth visceral folds. In the section e thus made, are seen the alimentary canal al with its collapsed walls, the neural canal , the noto- chord ch., the dorsal aorta A 0., and the vertebral veins V. The incision has been carried just below the upper limit of the pleuroperi- toneal cavity, consequently a portion of the somatopleure appears at the angle between the two third visceral folds. Almost embraced by the piece of somato- pleure is seen the end of the bulbus arteriosus A 0. In the drawing the nasal groove has been rather exaggerated in its upper part. On the other hand the lower part of the groove, where it runs between the superior maxillary process S. M. and the broad naso-frontal process, was in this particular embryo extremely shallow and indeed hardly visible. Hence the end of the superior maxillary process seems to join the inner and not, as described in the text, the outer margin of the nasal groove. A few hours later the separation of the two would have been very visible. B. The same seen sideways, to shew the visceral folds. Letters as before. process a rather bilobed appearance. These projecting portions of the fronto-nasal process form on each side the inner margins of the rapidly deepening nasal grooves, and are sometimes spoken of as the inner nasal processes. The outer margin of each nasal groove is raised up into a projection frequently spoken of as the outer nasal process which runs downwards to join the superior maxillary process, from w
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Keywords: ., bookcentury1800, bookdecade1870, bookpublisherlondo, bookyear1874
