HR. W. K. PARKER ON THE STRUCTURE AND 
200 
The fore part of the pterygoid bone is a large trowel (fig. 1, pg.), and it has used 
up the fore half of the cartilage which is its endoskeletal correlate. 
The hinder, forked part, whose forks form a right angle, clamps the pedicle and the 
quadrate pier; the former (pd.) is, by it, tied down to the skull, and would be found 
very small and not quite segmented from the basis-cranii. The latter (figs. 1-3, q., q.c.) 
is a strong retreating bar, with a very large trochlea below, and over this some bone 
derived from the qmidrato-jugal (q.j.). 
The annulus ( a.ty .) is large, thick, strong in the rim, broad, and complete. 
The mandible (fig. 3) answers to the strength of the upper face, and is quite 
normal. 
The stapes (fig. 4, st.) is a thick, oblique mass of cartilage, projecting externally in a 
boss ; it is hinged to the columella by a round tooth in the middle of its oblique scooped 
fore edge. The columella, without a proximal joint, is unossified at that part, which is 
nearly as long as that in front of the stapes; it is very oblique, is scooped, and has 
three teeth-like projections for its hinge in the stapes, so that these parts fit together 
like the valves of a “ Lamellibranch.” The shaft, altogether ( m.st .), is very gnarled 
and irregular, with a gentle arch ; its fore end is unossified and is cut off, by segmenta¬ 
tion, from the extra-stapedial. 
That part (e.st.) is spatulate, with a thin flange; this edge is notched off in front, 
and ends above in a small supra-stapedial (s..sA), that soon becomes a mere ligament. 
The hyoid band is confluent above (fig. 2, st.h .); it is broadish, and widens out 
below before it turns backwards. Both the “notch” and the basal plate (Plate 38, 
fig. 5, I)Ji.br.) are large—both long and wide; it has large ear-shaped front, and small 
styloid hind, lobes; the thyro-hyals ( tli.li .) are strong, and well bent, upwards, as they 
embrace the larynx. 
The investing bones are strong and thick, and scabrous externally; the fronto- 
parietals ( fp .) are both thick and wide; they have a square postorbital process, 
which articulates with the squamosal (sq.), are very wide behind, and become narrow 
.from before, backwards. Their orbital part overlaps the endocranium, and doubles its 
width behind. The fronto-sagittal suture is perfect, the fronto-nasal suture almost 
transverse. The nasals (n.) have the normal form and the Bufonine solidity; they 
meet along the middle, and only leave the end of the snout, and the ethmoidal wings, 
uncovered. 
The marginal bones (px., rrx., q.j.) are normal in form, but very strong and steep 
(fig. 3); the maxillary (mx.) has a wide palatine plate, which is widest where it arti¬ 
culates with the pterygoid. 
There is a large septo-maxillary (fig. 3, below e.n.) beneath the nostril and inside the 
maxillary. The squamosal (sq.) has a large, rough, ear-shaped supratemporal portion, 
and a long, retreating, descending bar. The parasphenoid (figs. 2, 3, pa.s.) is large and 
well-formed; its fore part is attenuated for some distance, the wings are splintery 
and angular, the hind part broad, and the median part thickened at the cross. 
