. Quain's elements of anatomy . he embryo op the dos ■with theHEART SEEN FROM BELOW. (From Kolliker, after Bisclioif.)Magnified. a, cerebral hemispheres ; 6, eyes ; c, mid-brain; d, man-dibular plates ; e, superior maxillary processes ; /, /, /,second, third, and fourth branchial or visceral plates ; g,right, li, left auricle of the hearb; k, right, i, left ventricle ;I, aortic or arterial bulb, -with three pairs of aortic or vasculararches proceeding from it. amiculo-ventricular aperture. As developmentprogresses the external division becomes more orless effaced, when the apex of the heart fo
. Quain's elements of anatomy . he embryo op the dos ■with theHEART SEEN FROM BELOW. (From Kolliker, after Bisclioif.)Magnified. a, cerebral hemispheres ; 6, eyes ; c, mid-brain; d, man-dibular plates ; e, superior maxillary processes ; /, /, /,second, third, and fourth branchial or visceral plates ; g,right, li, left auricle of the hearb; k, right, i, left ventricle ;I, aortic or arterial bulb, -with three pairs of aortic or vasculararches proceeding from it. amiculo-ventricular aperture. As developmentprogresses the external division becomes more orless effaced, when the apex of the heart formedby the left ventricle becomes more pointed, andthe whole heart takes somewhat of the conicalform which belongs to its advanced condition;but in the adult heart the depression is still perceptible as the inter-ventricular gToove, which, as is well known, varies considerably in depthin different cases. In some animals, as the rabbit, the temporary ex-ternal division of the ventricles is very apparent, while in others, as in. Fig. 775. Fig. 775.—Shows the position and form OF THE heart IN THE HUMAN EMBRYOFROM THE FOURTH TO THE SIXTH WEEK. A, upper half of the body of a humanembryo of nea,rly four weeks old (fromKolliker after Coste); B and C, anterior andposterior views of the heart of a humanembryo of six weeks (from Kolliker afterEcker) ; a, frontal lappet; h, mouth. ; c,ventral ends of the second and third bran-chial arches ; d, upper limb ; e, liver ; /,intestine cut short; 1, superior vena cava ;1, left superior cava or brachio-cephalicconnected with the coronary vein; 1, openingof the inferior vena cava ; 2, 2, right andleft auricles ; 3, 3, right and left ventricles ;4, aortic bulb. ruminants, there is very little of the external notching to be seen,and in them, as in birds, the heart very early assumes the conical dugong presents a remarkable example of the persistence of thecomplete external separation of the ventricles, and in the seal a tendencyhas been
Size: 1251px × 1996px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., boo, bookcentury1800, booksubjectanatomy, booksubjecthumananatomy
