The Ju'i'jn of Reptiles 



Even after a skeleton of such size had been 

 buried in the mud or sand, and this had be- 

 come stone, and, after long ages, finally brought 

 to the surface of the earth, there were many 

 opportunities for at least a part to be destroyed 

 before man came to collect it. Thus it happens 

 that while dinosaur remains may be common, 

 really good specimens are rare. 



The Sauropoda contain not only the largest 

 species of dinosaurs, but by far the largest of 

 known quadrupeds, creatures having twice or 

 thrice the bulk of the largest elephant, and 

 probably weighing from 15 to 20 tons. The 

 size and weight of these animals was so enor- 

 mous that it seems probable that they were 

 largely aquatic in their habits and passed 

 the greater part of their time in the water, 

 where this great bulk would be buoyed up. 

 This supposition is supported by the character 

 of the bones and various joints, which indicate 

 the presence of a great deal of cartilage, mak- 

 ing them loose-jointed, while in land animals 

 the joints are more firmly made and the bones 

 forming them fitted closely together. Still this 

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