OCR Text |
Show 156 ON THE SKULL OF THE GIRAFFE. [Jan. 19, which is largely filled up by the ethmo-turbinal bones shown in the centre of text-fig. 7 (p. 15:Ji). As in tlxe two previous figures, the vomer exhibits a trough on its upper surface ; its lateral projections enter into relation with the lowermost parts of the frontal bones as well as with the upper edges of tlxe palatines. A small process of tlxe maxilla extends backwards along the inner face of the jugal, and this process, although concealed by the jugal bone in text-fig. 4, is seen ixx section in text-fig. 7. T w o views are given of the skull cut in the direction of the line 4 in text-fig. 4, one (text-fig. 8, p. 154) looking forward, and the other (text-fig. 9, p. 155) looking backward. The plane of section passes obliquely down tlxe front part of the paired horns, so as to include the summit of the fronto-parietal vacuity on each side. In text-fig. 8 are seen the bony partitions that incompletely divide tlxe great fronto-parietal sinuses, and it will be noticed that these partitions are unsymmetrically disposed on the two sides. The Text-fig. 10. Ibr.map. l/as/rc. View, looking backwards, of the skull cut in the direction of the line 5 in text-fig. 4. One-third (linear) of the natural size. relatively small cranial cavity shows the cribriform plates in the distance. The section passes through the basisphenoid and alisphenoid bones, and the pterygoid bones (not their hamular processes) are seen ixx the distance flanking the inner surfaces of the lower wings of the alisphenoid bones. The zygomatic process of the squamosal is cut immediately behind the hindermost part of the jugal, but in the distance the jugal is seen rising behind the orbit to enter into extensive sutural connection with the post-orbital px-ocess of the frontal. The backward view seen in text-fig. 9 (p. 155) differs from the forward view of text-fig. 8 (p. 154) only in that in the distance are seen the upper parts of the paired |