. Anatomy, descriptive and applied. Anatomy. 72 SPECIAL ANATOMY OF THE SKELETON divisions of the crucial ridge is an eminence, the intemal occipital protuberance {yro- tuberantia occipitalis interna). It nearly corresponds to that on the outer surface, though it is often on a slightly higher level, and is perforated by one or more large vascular foramina. From this eminence the superior division of the crucial ridge runs upward to the superior angle of the bone; it presents a deep groove, .the sagittal sulcus (sulcus sagittalis), for the superior saggittal sinus. The margins of the groove give
. Anatomy, descriptive and applied. Anatomy. 72 SPECIAL ANATOMY OF THE SKELETON divisions of the crucial ridge is an eminence, the intemal occipital protuberance {yro- tuberantia occipitalis interna). It nearly corresponds to that on the outer surface, though it is often on a slightly higher level, and is perforated by one or more large vascular foramina. From this eminence the superior division of the crucial ridge runs upward to the superior angle of the bone; it presents a deep groove, .the sagittal sulcus (sulcus sagittalis), for the superior saggittal sinus. The margins of the groove give attachment to the falx cerebri. The inferior division, the intemal occipital crest (crista occipitalis interna), runs to the posterior margin of the foramen magnum, on the edge of which it becomes gradually lost; this Superior. Inferior angle. Fig. 40,—Occipital bone. Inner surface. ridge, which is bifurcated below, serves for the attachment of the falx cerebelli. It is usually marked by a single groove, which commences at the back part of the foramen magnum and lodges the occipital sinus. Occasionally the groove is double where two sinuses exist. A transverse groove (sulcus transversus) passes outward on each side to the lateral angle. The grooves are deep channels for the lodgement of the lateral sinuses, their prominent margins affording attachment to the tentorium.^ At the point of meeting of these grooves is a depression, the torcular^ (confluens sinuum), placed a little to one or the other side of the internal 1 Usually one of the transverse grooves is deeper and broader than the other; occasionally, both grooves are of equal depth and breadth, or both equally indistinct. The broader of the two transverse grooves is nearly •always continuous with the vertical groove for the superior sagittal sinus, 2 The columns of blood coming in different directions were supposed to be pressed together at this point iiorcular, a wine press).. Please note that these images are extra
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectanatomy, bookyear1913
