PROFESSOR OWEN ON INDIAN CETACEA. 27 
outward, overlapping the pterygoids (24), contract where they form the fore part of the 
foramen lacerum anterius and the optic foramina, beyond which they expand to 
support the orbital plate (fig. 3, 11’ ) of the frontal.’ 
‘The frontals (Pl. IX. figs. 1 & 2, 1, 11"), in great part overlapped, as in other Cetacea, by 
the maxillaries ( 21 ), show at their narrow exposed strip, extending transversely across the 
summit of the cranium, the persistant frontal suture, half an inch in length; from this 
suture the strip curves outward and backward, expanding beyond the interparietal ( 7* ), 
and then downward and forward, contracting and again expanding, to form the post- 
orbital process (figs. 1, 2, 12): this is triangular and three-sided, one facet being a 
continuation of the exposed strip, a second contributing to the temporal fossa, and a 
third to the orbit (or). In the temporal fossa, the frontal (fig. 1, 11) articulates with 
the parietal (7) and alisphenoid (6); in the orbit (ib. or), with the orbito-sphenoid 
(fig. 3,10) and malar (26); then, arching forward from the postorbital process, the 
frontal forms the superorbital ridge (fig. 1,11), and articulates anteriorly by a kind of 
gomphosis with the malar ( 26’); it is overlapped here, as on the cranium, by the max- 
illary (21"). The medial parts of the frontals (fig. 2,11) are united posteriorly with 
the interparietal (7*), anteriorly with the nasals (15 ). 
The vomer (ib. fig. 3, 13) extends forward to within an inch and a half of the end of 
the premaxillaries, and behind these it intervenes upon the bony palate between the 
maxillaries, along a strip of two inches extent and three lines across the broadest part. 
This palatal part of the vomer (13) is the lower convexity of the canal formed by the 
spout-shaped bone; the hollow of the canal is exposed at the upper interspace of the 
premaxillaries. Here, also, is seen, two inches behind the fore end of the yomer, the 
rough thick anterior border of the coalesced prefrontals (fig. 2, 14), which contracts as 
it passes into their upper border, forming the septum of the nostrils, expanding below 
and behind to form the back wall of the nasal passages(14’). At this part a trace of 
the suture between these foremost neurapophyses of the skull remains. ‘Their bifid spine 
—the small transversely extended subquadrate nasals (15 )—intervenes between the 
frontals (11) and prefrontals (14' ). The palatine bones appear on the palate as narrow 
strips (fig. 3, 20) wedged between the maxillaries, (21) and pterygoids (24), and united 
together beneath the vomer by a longitudinal suture of 3’” extent: then, passing out- 
ward and forward, after a brief contraction they suddenly expand and bend upward to 
line or form the mesial wall of the orbit, and again contract to articulate with the frontal 
at the superorbital fossa; the mesial borders of the palatines articulate with the vomer 
and prefrontals; and between the pterygoids and the vomer the palatines form the fore 
part of the lower half of the nasal passages. The orbital plate of the palatine sends off 
an outer thin lamina, which terminates by a free margin at the back of the orbit. The 
palatine plates of the maxillaries (21) unite together for about an inch in front of the 
palatines, then slightly diverge to give place to the vomer (33), which, however, does 
not sink to their level; in advance of the vomer the plates slightly diverge to their 
E2 
