DEVELOPMENT OF THE SKULL IN THE LACERTILIA. 
C01 
there is no distinction between the quadrato-jugal and the jugal; this also occurs where 
that specialization is seen for the last time, namely, in the huge “ Family ” or “ Order ” 
of the A ves JEgithognathce. 
In the lower face we miss the “jugulars” (the slabs under the floor of the mouth in 
Ganoid Fishes ); they are sub-mesial scutes, without an odd one ; here we get two bones 
that belong to the next row above them, and two more that show themselves at that 
line. 
For on the mandibular axis (articulo-M eckelian rod) the coronoid and splenial 
(Plate 43, fig 2, cr., sp.) are equivalent to ingrowing scutes next outside the “jugulars 
the “angulare” and “ surangulare ” also (ag., s.cig.,) appear on the inner face of the 
mandible. 
The dentary (d.) is the serial homologue of the maxillary and of the prsemaxillary; 
cot much of this large splint can be seen from its inner side (Plate 43, fig. 3), except its 
alveolar wall. 
The coronoid (cr.) is very high, the splenial (sjo.) long, large, and falcate ; the angulare 
(ag.) is a trough, and the surangulare ( s.ag .) a thick wall-plate to the hinder third of the 
mandibular axis. 
The ventral region of the fore-face has a pair of bones in front and an odd one 
behind; this pair are the vomers, and the odd bone the parasphenoid (Plate 42, fig. 2, 
v., pa.s). 
The vomers are large lanceolate splints, hollow above, and swelling, below; they are 
wedged in between the front half of the palatine portion of the maxillaries. 
These bones, with the septo-maxillaries, are to be seen again and again in their relation 
to the nasal labyrinth and nasal glands, in the sections of those parts (Plate 44). 
The cramio-facial axis ( p.e ., s.n.) rests on the harmony-suture formed by the right 
and left vomers ; their outer edge, behind, is the inner boundary of the inner nostrils 
( i.n.). 
The parasphenoid (Plate 42, fig. 2, and Plate 43, fig. 1, pa.s.) is a very small, sharp 
style, hollow above, convex below, and ankylosed, behind, to the basisphenoid ( b.s .); 
it only reaches half way to the vomer, exposing the base of the septum orbitarum. 
These are all the true dermal bones I can find in Lacerta ; but in the palate there are 
three pairs of bones formed in “ indifferent tissue ”—practically parosteal, but repre¬ 
senting ectosteal plates in many of the Ichthyopsida. 
The foremost pair, the palatines (Plate 42, fig. 2, pa.) belong to the palatine arch, 
and so do the outer bones or transpalatines ( t.pa .); but the hinder pair, the ptery¬ 
goids {pg.), belong to the symplectic outgrowths of the suspensoriiun of the mandible 
(quadrate). 
Where the “pith” of the palatine arch (“ etlnno-palatine ” cartilage) is well 
developed, as in Ganoid and Teleostean Fishes, there the bony deposit on it is a deep 
or ectosteal lamina. 
But as we ascend, there is less and less cartilage developed in the “ second pre-oral 
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