. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. CRANIUM. 729 work, which will be afterwards more fully ex- plained. The convexity of these domes is turned outwards and forwards in such manner that the circumference may abut against the longitu- dinal rib internally ; and, behind against the anterior rib in the base and a portion of the circumference of the lateral dome in the vault. That portion which is in the base^ is, as it were, pressed upwards to increase the space of the orbit, but not so much so as, at first sight, might appear; for on the external surface of t
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. CRANIUM. 729 work, which will be afterwards more fully ex- plained. The convexity of these domes is turned outwards and forwards in such manner that the circumference may abut against the longitu- dinal rib internally ; and, behind against the anterior rib in the base and a portion of the circumference of the lateral dome in the vault. That portion which is in the base^ is, as it were, pressed upwards to increase the space of the orbit, but not so much so as, at first sight, might appear; for on the external surface of the junction of the two portions there is an extraordinary development of the bone, which projecting over the face destroys the uniformity of surface and causes the orbitar portion to appear more elevated than it is in reality, and even to pass backwards at right angles with the other. Fig. The external surface of the frontal portion. in its upper two-thirds is smooth, of an equa- ble convexity and directed backwards; its inferior third is more vertical, and its convexity is interrupted by prominences. On the me- dian line it exhibits evidence of its original division into two parts, and this generally by a slight ridge, although in some instances there is a linear depression of equal indistinctness. This line is terminated by the nasal prominence, which has immediately above it a smooth tri- angular surface (glabella), and below it a rough notch for the articulation of the nasal and superior maxillary bones. From the centre of this notch there is a projection (pro- cessits tuisalis), on the fore part of which are fixed the nasal bones, and to its back part, which is grooved, the ethmoid bone is ap- plied. On either side of the median line there is, at about the distance of an inch where the middle joins with the lowest third of the bone, (he frontal eminence ( eminent ia frontalis, pro- cessus primi genii), which marks the centre of ossification, and the prominence of wh
Size: 1472px × 1697px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, booksubjectanatomy, booksubjectphysiology, booksubjectzoology
