SAUROPODA 



419 



of Morosaurus grandis. x -. 

 (After Marsh. ) a, First sacral 

 vertebra ; b, "transverse pro- 

 cess " (rib) of first sacral ; il, 

 ilium ; is, ischium ; nc, neural 

 canal ; pb, pubis. 



former stands almost vertically like that of elephants, and the 

 knee is scarcely bent in the erect position. The shoulder-girdle 

 consists of long scapulae, broad at the base and small, almost 

 square and perforated coracoids, which 

 latter fit into a pair of partly ossified 

 plates representing the sternum. 



Atlantosaurus immanis of the Upper 

 Jurassic of Wyoming and Colorado, is 

 supposed to have been 115 feet long, 

 perhaps the biggest and bulkiest of 

 all animals, the femur measuring more 

 than 6 feet in length and 2 in width , 



FIG. 96. Front view of the pelvis 



at the upper end. 



Morosaurus grandis, of the Upper 

 Jurassic of Wyoming, with allied forms 

 in the Purbeck and Wealden of 

 England, reached a length of 3 feet ; 

 in general appearance resembling Brontosaurus, but the sacrum 

 consists of four vertebrae only, and the ischia are bent back- 

 wards in their distal halves, so that their symphysis is formed 

 by the shafts instead of by their ends. 



Ornithopsis and Cetiosaurus, likewise huge creatures, from the 

 English Wealden and from the Great Oolite respectively, are 

 rather imperfectly known, although several species of each, 

 under many generic synonyms, have been described. 



Diplodocus longus, of the 

 Upper Jurassic of Colorado and 

 Wyoming, is almost completely 

 known. More than 40 feet 

 long, it had a head in its general 

 outlines not unlike that of a 

 horse, the skull being about two 

 feet long. The outer nasal 

 openings are confluent, elongated, 

 and lie far back on the top of the 

 skull. There is a pair of large antorbital, and a pair of smaller 

 lacrymal fossae. The teeth, long and slender, are restricted to 

 the anterior portion of the mouth, with many successors, which, 

 decreasing in size, lie on the inner or lingual side of the 

 functional tooth, like the cartridges in a repeating rifle. The 



FIG. 97. Skull of Diplodocus longus. 

 X T V (After Marsh.) 



