256 
ANOMODONTS. 
UPPER SURFACE OF THE SKULL OF A PAVEMENT¬ 
TOOTHED anomodont (J nat. size). 
toothed (Theriodont) Reptiles, the teeth, 
as exemplified in the figure of the skull 
of the African galesaur, are differentiated 
into incisors, tusks, and cheek-teeth; the 
latter frequently having three cusps 
ranged in a longitudinal series. Whether, 
however, this marked mammalian type 
of dentition is indicative of genetic affinity 
with Mammals, may be open to doubt, as it is quite as likely to be due to parallelism 
in development. Another modification is jn’esented by the Dicynodonts of England, 
Africa, and India, in which the jaws formed a horny beak, either destitute of 
teeth, as in the tortoises, or provided with a huge pair of tusks in the upper 
jaw; some of these reptiles being of 
gigantic size. A third group, known as 
Pavement-toothed, or Placodont Reptiles, 
which should probably be included in the 
order, are characterised by the presence 
of broad, flattened teeth on the palate and 
jaws, as shown in the figure on p. 5; the 
skull being very short and more or less 
triangular, with the double nostrils situated 
near the extremity of the muzzle, some 
distance in advance of the sockets of the 
eyes, which occupy a nearly central posi¬ 
tion. In all these forms, the skull has 
large temporal fossae in the hinder part of 
the upper surface; but in the Wall-toothed or Pariasaurian Anomodonts, as shown 
in the cut, the hinder part of the skull was roofed over by bone, in the manner 
characterising the Labyrinthodont Amphibians, to which these reptiles were allied ; 
a peculiar sculpturing of the surface of the skull being another point of resem¬ 
blance. In the species, of which the skull is figured, a number of spines surmounted 
the head; but these were wanting in the African pariasaur, which was a gigantic 
creature, with a somewhat frog-like head, an apology for a tail, and powerful 
short limbs, in which the toes were armed with long claws. 
UPPER SURFACE OF THE SKULL OF A WALL-TOOTHED 
anomodont (J nat. size). 
SKULL AND TEETH OF GALESAUR 
Anomodonts are met with in the Triassic rocks, and are represented by at 
least four well-marked subordinal types. In the first group, known as Mammal- 
