250 
MR. W. K. PARKER ON THE STRUCTURE AND 
The stylo-hyals are articulated (or partly confluent) with the ear-mass ; they are 
narrow, but the cerato-hyal (fig. 4, c.hy.) broadens up to the base, and the hypo-lryal 
( h.hy .) has its lobe behind, and not in front, as is the rule. 
The basal plate is relatively rather small and long, the front lobe smallish and 
rounded, the hind lobe normal; the thyrodiyals (t.hy.) are large, and not so divergent 
as in most kinds. 
The investing bones are as remarkable as the endoskeletal, and the two kinds are 
largely anchylosed together. The fronto-parietals ( f.p .) form, together, an oblong 
tract, largely confluent with the underlying bone, and not anchylosed together, except 
behind, the fronto-sagittal suture being straight and nearly perfect. The two bones 
are longest at the middle ; they form, in front, a low-angled projection ; they largely 
overlap the endocraniiun, especially over the optic passages, where they are unusually 
thick (fig. 3). The moderate temporal angle is ribbed, and where it rides over the 
ear-mass, and coalesces with it, it is crenate, along a concave edge. 
From one double canal-arch to the other (fig. 1, f.p.) the posterior parietal edge is 
straight; over the posterior canal the outlines are lost. I suspect that this part does 
not cover any secondary fontanelles. 
The large, broad, conchoidal nasals (n.) are wide apart, and send down a short, blunt 
facial process (fig. S, f.p. by mistake) ; they cover a third of the cartilaginous snout; 
as seen laterally, their edge is twice crescentically emarginate. 
The twin bones that finish the inferior and external facial arch ( px .) are wider than 
the rest of the arch, the maxillaries (mx.) soon narrowing in ; and the small quadrato- 
jugals (q.j.), which simply articulate with the quadrate, are narrower still; there are 
no teeth in the jaws. 
Both the nasal and palatine processes, as well as the body, of the premaxillaries, are 
small and feeble; the contiguous part of the maxillary, on each side, is rather high 
but does not reach the nasal at any point. The external nostrils, thrust out to the 
sides of the wide muzzle, are, however, well protected (figs. 3 and G). The inner, 
upper labial ( u.l h) is larger than the premaxillary; it is semi-oval, with a dilated base; 
it partly rests on the maxillary. The outer labial (u.l 2 .) is pedate below and rounded 
above ; it lies outside and below the nostril, and equals in size the projecting part of 
the roof (al.n.). 
Between the two labials there is a lozenge-shaped septo-maxillary (fig. 6, s.mx.), and 
inside the outer labial there is a second larger bone—a pre-orbital (p.ob.). This bone 
is two-thirds the size of the cartilage it is attached to, and of the same shape, but 
reversed; it has its counterpart in Pipci (Phil. Trans., 1876, Plate 62). 
The squamosal (figs. 1, 3, and 7, sq.) is better developed than in Callula; it is 
narrow, sigmoid above (fig. 1); is bent upon itself at less than a right angle; and the 
postorbital region of the upper part is hollowed out for the annulus and extra- 
stapedial. and helps to increase the size of the tympanic cavity. 
This structure, which exists in some degree in most Anura, comes in this case very 
