248' MR. W. K. PARKER ON THE STRUCTURE AND 



The occipital condyles {oc.c.) are small and postero-external ; not so much outside as 

 in Pipa, but very much more than usual. They look as much upwards as downwards. 

 The space between them is equal to the width of both, and is almost straight ; the 

 arch over the foramen magnum lies some way forwards, is very wide and somewhat 

 angular. The condyles, and the projection backwards, first by the posterior and then by 

 the horizontal canals (fig. 1, ep. by mistake), form a series of three irregular roimded 

 steps on each side, the outer steps passing, point by point, further fonvai'ds ; the 

 outermost are a little in front of the superoccipital margin. 



The auditory capsules are of the normal size, but they are very far apart, owing to 

 the great width of the hind skull, which is altogether bony, not only by the thorough 

 ossification of the cartilage right and left, above and below, Init also by anchylosis 

 of the inner with the outer elements, viz. : the fronto-pai'ietals and parasphenoid 

 {/.p., 2XI.S.). 



The tegmen tympani (fig. 1, t.ttj.) is broad in front and narrow behind, it is unossified ; 

 but the " canals " are all enclosed in bone. Below (fig. 2) there is the cai'tilaginous facet 

 for the small, very external "pedicle" (pd.), and this tract just serves for union with 

 the stylo-hyal (st.h.). But the fenestra ovalis (fig. 3, vh.) is well rimmed with bone; 

 and the floor of the hind skull is sinuously flat, with very little scooping in the ex- 

 occipital region, right and left ; the 9th and 10th nerves (IX., X.) have each theii' own 

 passage, and this twin-hole is behind, rather than beneath, the arch. The facial and 

 trifacial nerves (fig. 2, p)'>'-o., V.) also pass through a tAvin passage ; from that point to 

 the optic opening (II.) and its cartilaginous ring the skull is pinched. From the optic 

 hole, forwards, the skull widens steadily up to the "axils" of the ethmoid, where the 

 bone is gently scooped. Above, the inner bone can be seen there, in front of the 

 fronto-parietals, and behind and between the nasals (n.), whose outlines can just be 

 traced. The naked ethmo-septal bone is less than a third of the width of the roof; it 

 projects in front a little, at the middle, and then the fore part, for about a third of the 

 true nasal region, is unossified. 



Below (figs. 2 and 5), the bone reaches as far forwards, but it is triangular with ragged 

 sides ; the right and left angles pass into the palatines, which are thrown across, 

 inwards and backwards, as strong buttresses from the skull to the cheek {eth., mx.). 

 The broad hatchet-shaped palatine (^5«.) has ossified all its own overlying cartilage, the 

 arcuate blade of which passes outside, in the maxillary, along the edge of the internal 

 nostril {in.) ; this passage is large, oval, and looks forwards and inwards. The broad 

 muzzle is hollow at the end of the septum nasi, and swells, sinuously, to the outside. 

 The bones of the upper jaw {px., mx., q.j.) form a most elegant semi-oval — a bent bow 

 — which at its arch lies under the two-leaved tract of subnasal cartilage {s.n.l), and then 

 binds upon the endocranial bars at three places on each side, namely, on the palatines, 

 pterygoids, and quadrates [pa.,pg., q.c). 



The outer nostrils {c.n.) are on the sides of the wide muzzle, and are twice the 

 normal distance apart; they are weU protected by the nasal roof {al.n.) above, by the 



