104 
PEOFESSOE OWEN 0?? THE SCELEDOTHEEE. 
antero-median angles of the parietals are produced between the frontals, but to a less 
extent than the superoccipital in relation to the parietals. The temporal ridges are 
continued forwards from the parietal on to the frontal bones as far as the low obtuse 
postorbital process: in this com'se each temporal ridge makes three cmwes -oith two 
intervening angles, one at the fronto-parietal suture, the second not quite half-way between 
that sutm’e and the postorbital process. The frontal region of the cranium swells out a 
little above the zygomatic arch, but this affords no indication of cerebral development ; 
it is anterior to the true cranial cavity, and is due to the development of extensive frontal 
sinuses. The fore-part of the frontal terminates in an angle, wedged between the nasal 
and lacrymal bones, above the middle of the orbit : the descending plate forms the back 
part of the inner wall of the orbit, where it unites udth the maxillaiy, and then joins 
the palatine and pterygoid, terminating behind at the foramen ovale (ib. 1 ). The foramen 
rotundum (ib. r) is 2 inches 3 lines in advance, opening upon the suture between the 
frontal and pterygoid, and continued forwards by a canal containing the suture between 
the frontal and palatine. 
The palatine bones (Plate IX. 20) surround the posterior nasal apertm-e, and support 
the ridges (n, n) defining the lower boundary of that apertm-e : these ridges di-side the 
inner and under surface of the palatines into an intranasal and an infr-anasal part : both 
contribute to form the fore-part of the long and wide faucial fossa. 
The maxillary bone forms the major part of the narrow, transversely convex, bony 
palate (Plate IX. 21), the true palatines terminating anteriorly in a point opposite the 
penultimate molars (ib. iv) : the orbital plate of the maxillary (Plate VIII. fig. 2 , 21') 
ascends to articulate with the nasal (15), frontal (n), and lacrymal (73), and cfr-cumscribes 
the antorbital foramen (a), by an outstanding malar process, which affords a sutm-al 
surface behind for articulation with the malar bone (ib. fig. I, 26) : the maxillary then 
expands into a broad subquadrate facial plate (ib. fig. 2 a, 21), smooth and convex externally ; 
uniting above -svith the long nasal (is), behind -with the anterior half of the lacrpnal (73) 
and with the malar (26), and below and in front with the premaxillary (22). The outer 
alveolar wall makes a series of prominences corresponding -with the thi’ee anterior 
molars : the inner alveolar wall is a thin plate, forming a bony case for the deeply 
implanted parts of the molars and their matrices ; projecting in relief fr’om the iimer side 
of the facial and orbital plates. The length or depth of the fh-st alveolus (Plate IX. 1) 
is 3 inches 3 lines ; that of the second ( 2 ) is 3 inches 9 lines ; the succeeding ones (3, 4, 5) 
gradually decrease in depth. A canal is continued from that of the dental nerve above 
the alveoli, forward and downward to the lower and lateral part of the outer nostril. 
The alveoli, five on each side of the upper jaw, are close-set, with oblique apertures, 
the inner boundary descending lower than the outer one : their aggregate antero-posterior 
extent measures 4 inches 3 lines in one adult skull, 4 inches 6 lines in a second. The 
teeth (Plate IX. i-v), when in place, show wider intervals than the sockets ; the situation 
of the thick periosteum and dental capsule being occupied by the infiltrated matrix 
which, in the fossil under view, binds the tooth in its place : the shape of the socket 
