PROFESSOR OWEN ON INDIAN CETACEA. a9 
the “hamular” one; the outer portion, partly marked off by a ridge from the palatine 
plate of the inner portion, bends outward and backward with a convexity toward the 
palate, then slightly inward, as if twisted on itself, and, expanding at its upper attach- 
ments to the pre-, orbito-, ali-, and basi-sphenoids, terminates by developing the 
deep and broad plate (ib. 24’) which appears to continue forward the otocranial 
plate (5') of the basioccipito-sphenoid. The inner surface of the outer part of the 
pterygoid is vertically concave to its posterior lamella, which is so bent as to make that 
surface somewhat convex: the concave channel prolongs backward the nasal passage 
(w) beyond the septum. A semicircular emargination divides the posterior subvertical 
plate from the palatine portion (24) of the pterygoid. The total length of the pterygoid 
is 4 inches 8 lines; the breadth of the pair of bones posteriorly is 5 inches; the sutural 
union of the pterygoid with surrounding bones persists'. 
The malar bone (PI. XII. fig. 1, Pl. XIII. figs. 1, 2, 26) is represented in the present skull 
by the portion of that in Delphinide (Pl. IX. figs. 1, 3,26’) which is wedged like a 
lacrymal? between the frontal (11’) and maxillary (21”) at the upper and fore part of the 
orbit (07): it is here of a subtriedral conical shape, with its base notched for a wedged 
union with the maxillary above, and concave where it joins the frontal behind: the inner 
angle of the base curves forward, with a slight twist, to unite again with the maxillary 
at the inner side of the malo-maxillary fissure (4). The outer facet of the malar is 
slightly concave vertically, convex transversely: the antero-internal facet is concave in 
both directions, except where it curves anteriorly round the obtuse angle between it and 
the outer surface: the internal or orbital surface is the narrowest, and is conxex trans- 
versely, and straight vertically. The apex is subbifid, the outer part (Pl. XII. fig. 1, z) 
low and obtuse, the inner one longer, produced downward and rather backward, and 
terminating less obtusely; but there is no sign of any slender zygomatic style having 
been continued from this part, as in Phocena brevirostris (Pl. TX. fig. 1, 26). It would 
seem, therefore, that the zygomatic processes of both malar and squamosal were short and 
free; they are separated by an interval of more than 2 inches in the present skull, which 
interval I found occupied by a ligament (“sclerous” state of malar) in a young Cachalot®. 
The squamosal forms an articular surface (PI. XIII. fig. 2, 27,7) for the mandible, look- 
1«The pterygoid, which is double the size of the palatine, extends backward to the basioccipital, articulating 
in that course by its expanded upper border with the pre-, basi-, and ali-sphenoids ; from this border the bone 
descends arching inward toward its fellow, which it joins along the anterior half of its extent: the remain- 
ing free border is divided from this by a deep notch, and circumscribes the posterior bony aperture of the 
nostril.” —Physeter macrocephalus, op. cit. p. 443. 
2 Tf this be the homologue of a lacrymal, it is not merely confluent, but connate with the malar. 
3 «The malar is moderately long and slender, bent upon itself at an acute angle; the upper portion, 
wedged between the maxillary and frontal, is the thickest; the lower and more slender branch is bent down- 
ward and backward, circumscribing the orbit anteriorly and below, and is connected by ligament to the 
zygomatic process of the squamosal. There is no lacrymal bone.”—Physeter macrocephalus, op. cit. p. 444. 
