diameter of the cranium, according to Dr. "W.'s method of measurement, being considered 100, 43.9 represents the distance from the anterior edge of the foramen magnum to the most projecting part of the occiput. In the crania of twenty whites, Dr. W. found the mean index of the fora- men magnum to be 45.6. " A third articular surface ex- ists in the middle of the fore edge of the foramen magnum, and corresponds with the apex of the odontoid process of the axis. It is a smooth, oval depression, with slightly raised borders, and has the appearance of having been covered with an articular cartilage ; it is supported by a very slight elevation of bone, as in the cases of condylus tertius, described by Dr. Halbertsma. When viewed from behind, this cranium is remarkable for the manner in which the lateral walls slope toward the vertex." 1847.
Dr. J. C. Warren.
1552. A second specimen. " Supposed to be from a subject about three years old. The sagittal suture is wholly ob- literated ; the median ridge and the vascular openings, with a peculiar radiated appearance, as also the appear- ance of a median centre of ossification, exist here in a marked degree. This cranium is remarkable for its great length ; the index of breadth being only 62.6. The fora- men magnum is central ; the increase in length having taken place equally forwards and backwards. This also appears .from the equal protuberance of both forehead and occiput. The occipital region presents outwardly, as it were, a cast of the cerebellum ; two bulgings, corresponding with the lateral lobes, project downwards beyond the tips of the mastoid processes. The hinder lobes of the cere- brum can also be traced in a similar way, and form a third bulging in the outer surface of the occiput." 1847.
Dr. J. C. Warren.
1553. A third specimen. Cranium of a foetus, in which the de- formity from elongation of the head was, in the recent state, very strongly marked.
" The lengthening of the head is almost wholly for- wards ; the index of the foramen magnum being only 32.2. The .anterior fontanelle is largely open, and is prolonged between the frontals, by a space with parallel sides, twenty
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