180 THE STORY OF REPTILE LIFE. 



at least one distinct order." An alliance with 

 the Anomodonts has recently been suggested, 

 but this is not likely to receive much favour. 

 They reached the dignity of a dominant race 

 during the Jurassic and Cretaceous periods, 

 succeeding the Anomodontia, and disappearing as 

 the Mammalia commenced their era of ascendancy. 

 These singular creatures, like other notorious 

 groups which preceded and followed them, make 

 their first appearance on the stage in a compara- 

 tively humble guise, the earliest known forms 

 being small carnivorous types, having the jaws 

 well armed with cutting teeth lodged in sockets, 

 and hollow bones, like those of birds. In the 

 course of the evolution of the group we find 

 specialisation taking place in many directions. 

 Originally quadrupedal, some became bipedal, 

 developing enormous hind-limbs, and reducing 

 the size of the fore-limbs, a method of pro- 

 gression which, at different times and in various 

 places, during the history of this group, deve- 

 loped into leaping, as in the Kangaroo and 

 Jerboa of to-day. Witnesses to this we have 

 in the remains of ffallopus, from the Jurassic of 

 Colorado, and Compsognathus, a beast about the 

 size of a fowl, from the Lithographic Stone of 

 Solenhofen in Bavaria. As the body increased 

 in size, attaining that enormous bulk which has 

 made these creatures famous, such agility became 

 impossible. Indeed, it is now generally believed 

 that the huge size of the very largest species 

 made life on land almost impossible. But to 

 this we shall return. There is good evidence to 

 show that the larger species at least of these 



