yo EXTINCT MONSTERS. 



Professor Marsh and his comrades, in the far west of America, as 

 well as by the researches of English geologists, assisted by the 

 labours of many ardent collectors of fossils, in this country. Some 

 of these may now be briefly considered. 



In Plate V. we have endeavoured to give some idea of a 

 huge thigh-bone (femur) belonging to the truly gigantic Dinosaur 

 called Atlantosaurus. It is six feet two inches long, and a cast 

 of it may be seen in the fossil reptile gallery of the British Museum 

 of Natural History (Wall-case No. 3). It should be mentioned, 

 however, that the original specimen is partly restored, so that its 

 exact length to an inch or so is not quite certain. In our illustra- 

 tion it is shown to be a little taller, when placed upright, than 

 a full-grown man. Professor Marsh, the fortunate discoverer 

 of this wonderful bone, calculates that the Atlantosaurus must 

 have attained a length of over eighty feet ! and, assuming that it 

 walked upon its hind feet, a height of thirty feet ! 



It doubtless fed upon the luxuriant foliage of the sub-tropical 

 forests, portions of which are preserved with its remains. Besides this 

 thigh-bone. Professor Marsh has procured specimens of vertebrae 

 from the different parts of the vertebral column ; but no skull or 

 teeth. The vertebrae are hollowed out much in the same way as 

 those of Brontosaurus. The fore limbs were large, as in the latter 

 animal ; and the extremities of the limbs were provided with claws. 

 Taking all present evidence, it appears that the Atlantosaurus 

 bore a general resemblance to its smaller contemporary. We can 

 therefore form a fairly good idea of its aspect and proportions. 



The same Jurassic strata from the Rocky Mountains ' have 

 yielded remains of another big Dinosaur, belonging to Che same 

 family. This genus, which has been named the Apatosaurus, is 

 represented by a nearly complete skeleton, in the Yale College 

 Museum ; and is fortunately in an excellent state of preservation. 

 Another species, of smaller size, though not so complete, adorns 

 the same collection. This was about thirty feet long, and is 

 known as Apatosaurus grandis. 



