THE EXTINCT DINOSAURS 



2395 



short foot bones, frequently terminating in hoof-like toes, and the habitually 

 quadrupedal gait. Commencing in the British L,ias, these extraordinary rep- 

 tiles continued throughout the Secondary period, and seem to have attained 

 their maximum develop- 

 ment at the close of the 

 Cretaceous epoch in the 

 United States. Of the 

 armored forms, the huge 

 stegosaur of the English 

 Oxford, and Kimeridge 

 Clays, and the correspond- 

 ing rocks of the United 

 States, was characterized 

 by the possession of large 

 quadrangular bones, 

 which are believed to 

 have been arranged in a 

 vertical position down the 

 middle of the back, while 

 the tail was protected by 

 some formidable spines, 

 as shown in the greatly 

 reduced restoration of the 

 skeleton given on p. 2360. 

 Still more strange were 

 the somewhat later horned 

 dinosaurs ( Ceratops, etc. ) , 

 of which two views of 

 the skull and a more 

 reduced restoration of the 

 skeleton are here given. 

 In these extraordinary 



a. nostrils; f. brain; h. horn; n. nasal bones; p. chin bone; r. extremity 

 f upper jaw. After Marsh. 



UPPER AND SIDE VIEWS OF THE SKUI.I, OF A HORNED DINOSAUR. 



creatures the hinder part 

 of the head was provided 

 with a pair of bony horn- 

 like projections, which were doubtless insheathed during life with hollow horns, like 

 those of oxen; and there was also a single horn of variable size on the nose. The 

 skull was further remarkable for the expansion of its hinder extremity into 

 a fan-like shield overhanging and protecting the vertebrae of the neck. Some 

 idea of the huge dimensions attained by these dinosaurs will be conveyed by the 

 statement that an immature skull of one of the species measures upward of six 

 feet, while fully adult ones must have been considerably larger. The extraordina- 

 rily small size of the brain of these creatures is indicated in the lower figure of the 

 skull. Externally the bodies of these dinosaurs were protected by granules and 

 plates of bones, which, like those of crocodiles, were probably overlain with horny 



