A clinical study of the skull / by Harrison Allen.

  • Allen, Harrison, 1841-1897.
Date:
1890
Catalogue details

Licence: Public Domain Mark

Credit: A clinical study of the skull / by Harrison Allen. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    80/90 (page 74)
    were slightly curved. They were undoubtedly developed in the direction of the vertical fibres of the temporal muscle.1 The pneumatic process of the occipital bone was met with in six2 instances. In six of these the process was on the left side. The paroccipital process may be bent inward and flattened,3 aud in one instance was found to articulate on the left side with the atlas.* Regions of great density of bone structure.—The disposition for some parts of the cranium to show dense ivory-like thickenings is very noticeable. The causes which induce the vascular cancellous tissue to assume greater density with diminution of blood-vessel supply would be interesting to trace. Four localities are named for the occurrence of this change—1st, the petrous portion of the temporal bone; 2d, the inner or vitreous plate of the bones entering into the composition of the vertex;5 3d, the margins of the jugular foramen, notably the anterior; 4th, occasionally in the interior of sinuses, as seen in the maxillary and ethmoid sinuses. The disposition to ivory-like density is often morbid (this prob- ably includes the third and fourth groups as given above), and may even be present in the vitreous plate of the vertex. Scarcely a cranium can be found in our dissecting-rooms in which solid nodules are not found in some part of the interior of the cal- varium, especially at the frontal portion on either side of the me- topic line. Many individuals exhibit dense, white, low eminences of the general internal surface at the region of the bregma. They are lozenge-shaped and measure four to six centimetres in diameter. ^ee No. 1271, North American Indian; No. 742, Mandan; No. 963, negro. 2No. 1229, TJpsarooka; 20, Bengalee; 78, 35, Menominee; 204, Che- nook; 707, Seminole. 8 See skull of Alaskan in museum of Princeton College, N. J. * No. 706, German. 5 This is seen to be the case to a remarkable degree in the skull of an Esquimaux (No. 1554) in the Army Medical Museum.