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DBS. A. CAKTE AND A. MACALISTEE ON THE 
of the frontal and extending back as far as the anterior border of the pterygoid bone ; 
the groove for the nasal nerve lay between this bone and the base of the vomer, with 
which latter this plate was closely united. Fourthly, the large nasal lamella, situated in 
the median line ; it was thicker below than above, and was fitted into the deep longitudinal 
channel excavated in the vomer. 
The superior maxillary bone in shape resembled a ploughshare, having its apex some- 
what rounded in front, and its base behind. It presented four surfaces, one external or 
facial, a second internal or nasal, a third inferior or palatine, and a fourth posterior. 
The external or facial surface was triangular in outline, slightly convex and smoothish ; 
it was prolonged upwards and backwards into a nasal process, which articulated by foli- 
aceous indigitations with a similar arrangement of osseous plates on the frontal bone. 
This surface was marked by eight or nine irregularly placed foramina, from which chan- 
nels passed outwards and downwards for the transmission of blood-vessels, &c. to the 
baleen plates ; the infraorbital foramen was large and situated at the junction of the nasal 
process with the body of the bone ; from this a canal passed, at first downwards and out- 
wards, then backwards and inwards ; through this canal the superior maxillary nerve and 
vessels made their exit to supply the integument and muscles on the side of the snout. 
The inner or nasal surface was slightly concave, and was directed upwards and inwards ; 
it was furrowed for the intermaxillary bone above, and presented a groove for the upper 
edge of the vomer, which was overhung by a sharp bony ridge : two oblique foramina, 
which passed inwards and forwards into the base of the bone, were visible here ; these 
were for the transmission of the nutrient vessels. The inferior or palatine surface was 
deeply concave, and exhibited fifteen oblique apertures, the orifices of channels for the 
transmission of blood-vessels which passed in various directions, radiating and grooving 
the surface of the bone. 
The posterior temporo-frontal surface or base was irregular, and divided into two 
unequal surfaces by large excavated vascular foramina communicating with the aper- 
tures already described on the various other surfaces ; the upper plane articulated with 
the frontal and formed the anterior boundary of the temporal fossa ; the lower was free, 
and passed under the supraorbital plate of the frontal bone without coming into actual 
contact with it. The upper or nasal edge was marked by a shallow groove for the inter- 
maxillary bone ; the posterior border, for about one-sixth of its extent, was sharp and 
harmonized with the outer edge of the nasal bone. The inner or palatine edge was 
concave, and its anterior four-fifths overlapped the vomer ; its posterior fifth was deeply 
hollowed, and was covered by the palate-bone. The outer edge was sharp and convex, 
and was prolonged into a blunt zygomatic spur, behind which it extended downwards 
and backwards below the level of the bone for 3^- inches, where it formed the anterior 
border of the orbit ; this spur was separated from the outer edge by a deep groove, and 
above internally its continuation formed the anterior boundary of the temporal fossa. 
The vomer was a long deeply channelled or spout-like bone, concave on its upper 
aspect, narrowing anteriorly, and convex beneath, forming a blunt median ridge that 
