DRAGONS OF OLD TIME 131 



powerful. Just as the birds and beasts (quadrupeds) of to-day 

 show an almost endless variety, according to the circumstances 

 in which they are placed, so that great and powerful order of 

 reptiles we are now considering ran riot, and gave rise to a 

 variety of forms, or types. 



Various attempts have been made to classify Dinosaurs and 

 arrange them in family groups. But considering how imperfect 

 our knowledge is of this very great and important order of 

 reptiles, it is well to bear in mind that all such attempts are 

 provisional and temporary. Much might be said in favour of a 

 complete rearrangement of the classification usually adopted, 

 which is that of the late Professor Marsh. As at present con- 

 stituted, they appear to make a very artificial group. 



The order is usually divided into three sub-orders, as follows : 

 (1) Theropoda, or beast-footed ; (2) Sauropoda, or lizard-footed ; 

 (3) Predentata, Ornithopoda, or Orthopoda. We shall follow 

 this arrangement (used by von Zittel and others) but merely 

 for convenience. Dr. H. Gadow raises them into a sub-class, 

 making the above groups into orders, which perhaps is better. 



But it may be that Dinosaurs are not a homogeneous group. 

 Perhaps some day the sub-order Sauropoda may be taken away 

 altogether and placed with, or at least, near to the crocodiles, 

 which they resemble in some ways. But Dinosaurs are strange 

 beasts, very puzzling to the naturalist ; and, much as our know- 

 ledge of them has been extended, future discoveries may bring to 

 light forms quite as strange as those already known. Doubtless 

 hundreds of specimens lie awaiting discovery in the unexplored 

 fields of Asia, Africa, and South America. Dinosaurs also show 

 obvious resemblances to the Ehyncocephalia and the Theromorpha. 

 But nobody can say exactly where they should be placed. If we 

 try to construct a genealogical tree of the reptiles we must put 



