228 
MR. W. K. PARKER ON THE STRUCTURE AND 
equals that of a typical Batrachian whose tail is rapidly shortening; in others it nearly 
equals the skull of the adult in those high kinds; the ossification especially is 
defective here, as in some of the dwarfed kinds of Frogs. The foramen magnum is 
large, and the roof covers it well; the occipital condyles ( oc.c .) project scarcely at all, 
and are postero-inferior. The roof runs half way to the ethmoidal region, and has no 
secondary fontanelles; the great space (fo.) is as long as the hinder “tegmen,” and is 
very elegant in shape, like the cordate leaf of Nymphosa alba. 
The tegmen cranii is no wider in front than at the sides, where it is unusually well 
developed. The ovoidal auditory capsules are well turned outwards, and are large; 
beyond them the tegmen tympani (t.ty.) is a small squarish lobe, as in the last two 
kinds. There is a little calcification above (fig. 1) but more below (fig. 2, b.o.), and that 
tract is wide, and rapidly widens forwards, for the ex-occipitals (e.o.) are only large 
reniform patches that enclose their own nerves (IX., X.); they creep up between the 
arch and the capsule so as to show a little above (fig. 1). The prootic also ( pr.o .) is 
a curved band just margining the foramen ovale (V.), and creeping along the capsules 
for some distance above and below (figs. 1, 2).* 
The mid skull is broad, lessening gently forwards, and bulging; it is moderately 
high, and is wholly unossified, as is also the fore skull and nasal region; this is equal 
to the hind skull in axial extent; the mid skull is one-third longer. The large 
baggy nasal roofs lying back over the eth mo-palatine bar (fig. 1), and the wide trabe¬ 
cular floor (fig. 2, on each side of s.n.) are quite juvenile in character; the nostrils 
(e.n.) are sub-tubular and projecting ; they are wide apart, and protected by the normal 
valves ( u.V-.u.l 2 .). The rostrum ( p.n .) is also in its first stage, a mere decurved lip of 
cartilage; the pro-rhinals ( p.rh.) are small and rudimentary. 
The palato-suspensorial arch is delicate, and continues to the pedicle and quadrate 
( pd ., q.), the pre-palatine is sharp, the post-palatine ( pt.pa .) marked off from the ptery¬ 
goid by a sharp lobe (a juvenile character), and the eth mo-palatine has a fine thread 
of ossifying perichondrium under it ( e.pa., pa.). 
The delicate bifurcate pterygoid (pg.) runs along inside the post-palatine bar, gives 
off a pedate fork for the short pedicle ( pd .), and binds itself to the suspensorium (q.) 
behind ; in its fork we see the small, round Eustachian opening ( eu .). 
The quadrate condyle (q.c.) is a perfectly normal trochlea, oblique, with the front 
elevation small; above it the “orbitar process” ( or.p.) is retained, as an ear-like lobe, 
which is nearer the condyle (q.c.) than the otic process (fig. 1, above or.p.) ; this is a 
rare character. The annulus ( a.ty .) is large (quite of the typical size), and is very 
perfect above, as a ring. The mandible (fig. 3) is long and very perfect in all its parts. 
The stapes (fig. 5, st.) is thick, oval, with an oblique, antero-superior, grooved emar- 
gination for articulation with the columella; it is also umbonate. The columella 
(fig. 5) only wants segmentation of the large cartilaginous proximal lobe (m.st.) to 
* The continuous bony tract right and left, in the last, is due, as this skull shows, to coalescence of 
the two normal centres. 
