414 
MR. W. K. PARKER ON THE STRUCTURE AND DEVELOPMENT 
(./•) The form and relations of the nasal gland (n.g.) are involved in the foregoing 
details : — 
The parts remaining to be described are the bones that belong to the maxillo- 
palatine, mandibular, and hyoid arches ; the latter has only two traces, the spike of 
the columella (co.) and the minute style-hyal scale (Plate 32, figs. 1, 2, st.li.) ; but 
the parts round the mouth are greatly developed and modified. 
The palatines, transpalatines, and maxillaries are the three elements of the second 
pre-oral arch ; the first of these (Plate 32, figs. 1, 2, pa.) is a slightly inbent rod 
loosely attached to the sides of the nasal region in front, and overlapping the apex of 
the pterygoid ( pg .) behind. 
Its ethmoid process (Plate 33, figs. 13, 14, e.pa .) is much flatter than in the early 
stage ; it lies over the middle nostril. 
The maxillary (mx.) is a narrow, arcuate, dentigerous bone ; it bounds the gape, 
running forwards from the pre-maxillary to a point opposite the post-orbital region. 
Lying on the jugal end of the maxillary is the blade of a curious hatchet-shaped 
bone, the transpalatine ( t.pa .) : its handle lies on the outer edge of the middle of the 
pterygoid. 
The mandibular arch is yoked on to the maxillo-palatine by means of the pterygoid 
(pg.) : this bone only answers to the bony plate of the Salamander’s or Frog’s ptery- 
goid ; there is no corresponding cartilage budding forth from the quadrate. 
This is a long falcate bar, widest in the middle, gently convex below, and slightly 
scooped above ; it is obliquely attached to the under face of the end of the palatine, 
and then stretches backwards and outwards, clamping the quadrate above and inside 
its hinge, and reaching to the end of the long angular process of the mandible 
itself (ar.). 
In the gigantic types (Python, &c.) there are large “ basi-pterygoid processes,” on 
which the pterygoid glides ; here these are not distinct. 
The suspensorium or quadrate (q.) is let down, backwards, by its own splint, the 
squamosal ( sq .). This latter bone lies over the auditory mass, reaching to the parietal ; 
it is oblong and rounded in front, and behind it is bevelled and faced, there, with 
articular cartilage. 
The supra-temporal scale is now ankylosed to the squamosal. 
The broad, oblique, top end of the quadrate (q.) glides over the articular face of the 
squamosal, and then lessening, this bone becomes a rib-like rod, with a cylinclroidal 
condyle for the excavation in the articulare (ar.). 
This latter bone has ossified much of Meckel’s cartilage, and is invested with the 
long angular and surangular, both narrow and pointed at both ends (ag . , s.ag.). 
There is a partial hinge on the ramus opposite the end of the maxillary, dividing 
the bar so as to leave only two-fifths in front and as much as three-fifths behind. 
Externally, the dentary (d.) overlaps this part by its forks ; but, on the inside, 
the splenial and coronoid (sp., cr.) — the latter is the larger bone — meet each by a broad 
