The Triassic rocks of South Africa and India have yielded the remains of some extraordinary Reptiles, which have been placed by Professor Owen in a separate order under the name of Anomodontia.  The two principal genera of this group are Dicynodon and Oudenodon, both of which appear to have been large Reptiles, with well-developed limbs, organised for progression upon the dry land.  In Oudenodon (fig. 154, B) the jaws seem to have been wholly destitute of teeth, and must have been encased in a horny sheath, similar to that with which we are familiar in the beak of a Turtle.  In Dicynodon (fig. 154, A), on the other hand, the front of the upper jaw and the whole of the lower jaw were destitute of teeth, and the front of the mouth must have constituted a kind of beak; but the upper jaw possessed on each side a single huge conical tusk, which is directed downwards, and must have continued to grow during the life of the animal.

[Illustration:  Fig. 154.—­Triassic Anomodont Reptiles.  A, Skull of Dicynodon lacerticeps, showing one of the great maxillary tusks; B, Skull of Oudenodon Bainii, showing the toothless, beak-like jaws.  From the Trias of South Africa. (After Owen.)]

It may be mentioned that the above-mentioned Triassic sandstones of South Africa have recently yielded to the researches of Professor Owen a new and unexpected type of Reptile, which exhibits some of the structural peculiarities which we have been accustomed to regard as characteristic of the Carnivorous quadrupeds.  The Reptile in question has been named Cyanodraco, and it is looked upon by its distinguished discoverer as the type of a new order, to which he has given the name of Theriodontia.  The teeth of this singular form agree with those of the Carnivorous quadrupeds in consisting of three distinct groups—­namely, front teeth or incisors, eye teeth or canines, and back teeth or molars.  The canines also are long and pointed, very much compressed, and having their lateral margins finely serrated, thus presenting a singular resemblance to the teeth of the extinct “Sabre-toothed Tiger” (Machairodus).  The bone of the upper arm (humerus) further shows some remarkable resemblances to the same bone in the Carnivorous Mammals.  As has been previously noticed, Professor Owen is of opinion that some of the Reptilian remains of the Permian deposits will also be found to belong to this group of the “Theriodonts.”

[Illustration:  Fig. 155.—­Supposed footprint of a Bird, from the Triassic Sandstones of the Connecticut River.  The slab shows also numerous “rain-prints.”]