598 
MR. W. K. PARKER OK THE STRUCTURE AND 
For comparison with it we may conveniently take the existing Ganoids ( Acipenser, 
Polypterus, Lepidosteus, &c.), and also the very instructive skulls of the “ Siluroid ” 
Teleosteans —such as Callichthys, Doras, and Clarias. 
Even at this height, in the culminating Lacertian, the stone does not quite cover the 
well’s mouth—the old familiar “ fontanelle ” is to be seen at the middle of the ankylosed 
sagittal line (Plate 42, fig. 1 ,fo.) ; in Clarias capensis it is further back, and there is 
another longer chink between the frontals ; in the Chammleon the single hole is f rontal. 
The fused parietals (p.) make a large square roof-shingle; the outer edge joins the 
largest supra-temporal (s.t 1 .) by a toothed suture ; the coronal suture also is toothed, 
and almost straight across; the occipital edge is shelving, and each hind angle sends 
down a crescentic “ horn.” 
The parietal plate so rests upon the narrow ascending superoccipital (fig. 4 , p., s.o.) 
as to leave between it and each “ horn ” an oval supra-temporal space ; a covered shed 
for the temporal muscle. 
Each horn rests, by an enlarged, trilobate root, upon the extended auditory masses 
(parotics) ; the horns are subcutaneous and smooth; the rough top of the bone is 
marked by the overlying scales, which in both parietals and supra-temporals, are in 
non-conformity with the cranial sutures (Plate 42, fig. 1). 
The frontals (Plate 42, fig. 1,/.) are longer, narrower, and more irregular than the 
parietals ; they have retained the frontal suture ; in the hinder third of which there is 
a, fossa, the scarcely-closed anterior “ fontanelle ” of Clarias. 
The frontals are broadest at the coronal suture; they then narrow and widen again 
twice, and are narrowest in front at the transverse nasal suture. 
But for the curious atavistic multiplication of scutes, the frontals of Lacerta would 
have been very large, yet, as in many archaic Vertebrata, the super-orbital region has 
its own bony eave, composed of two rows of tiles (figs. 1, 3, s.ob.). 
Of these the inner row is composed of four, the hinder piece small, the foremost 
smaller, and the two others large ovato-acuminate scutes. 
Outside these, a second row of five smaller oblong scutes finishes the overhanging 
“ brow; ” four of these are swper-orbital, and the last is turned downwards as a post- 
orbital bone. 
But the most constant “post-orbital” (“post-frontal,” Cuv.) is as large as the 
corresponding parietal moiety along which it is placed ; it is a large convex sub-oval 
scute, reaching from the orbit to the occiput (Plate 4, figs. 1-5, pt.o.). 
Outside the hinder part of this bone is another less than half its size (s.t. 1 ) ; it is an 
irregularly oval scute with its pointed end forwards; above, it overlaps the great post¬ 
orbital, and below, the ascending, pointed part of the squamosal (sq.). 
This latter bone is a sickle, whose pointed end runs forward below the edge of the 
hinder half of the post-orbital, and within the first supra-temporal; its thick end is 
turned downwards, and is articulated to the head (or “ otic process ”) of the quadrate 
(sq., q.) ; that joint has a synovial cavity lined with cartilage. 
