. The American journal of anatomy . d along in the sheath-like covering of thefiber A to the point where this change takes place and the sheathis seen to be directly continuous with the perimysium of the heartmuscle. This mode of transition of a fiber into a group of muscle cells,is apparently one of the ways in which the sino-ventricular sys-tem may terminate within the myocardium of the has discussed other forms. While an inquiry into theseterminal mechanisms and the histology of the same, has not beenthe special object of this investigation, nevertheless, in tracingout the
. The American journal of anatomy . d along in the sheath-like covering of thefiber A to the point where this change takes place and the sheathis seen to be directly continuous with the perimysium of the heartmuscle. This mode of transition of a fiber into a group of muscle cells,is apparently one of the ways in which the sino-ventricular sys-tem may terminate within the myocardium of the has discussed other forms. While an inquiry into theseterminal mechanisms and the histology of the same, has not beenthe special object of this investigation, nevertheless, in tracingout the ramifications of injections, into the sheath, the above THE SHEATH OF THE BUNDLE OF HIS 67 transition was observed. Such a transition could, perhaps, beconsidered a means to offset the great numerical disproportionwhich must exist between the fibers of the atrio-ventricular systemand the heart muscle fibers. Fig. 5 shows a camera lucida drawing from the auricular region—the Knoten—in a section of tissue from beef heart no. Fig. 4 Camera lucida drawing; section of ventricular myocardium, beef and B, Purkinje fasciculi; C, injection material within connective tissue sheath;D, cardiac muscle fibers; E, fasciculus of heart muscle fibers in which fiber A ter-minates. X 275. Point A shows the auricular muscle fibers cut in cross these, bundles of fibrillae pass off to enter a point of unionfor many such fibril fasciculi, which place Tawara has called anode. In this nodal point the fibrils are seen as confused strandscoursing in many different directions. The clear spaces G repre-sent the indentations of the node which have been cut in the sec-tioning, and within which the connective tissue nuclei can be 68 RUSKIN M. LHAMON
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectanatomy, bookyear1912
