Page:The Osteology of the Reptiles.pdf/311

Rh twenty-seven presacrals. The pubes are massive and meet in a large ventral symphysis. Carpals and tarsals reduced, feet preaxial. Limb bones cancellous in structure. From about fifteen to about ninety feet in length.

. Spines of dorsal vertebrae simple, not furcate. Front limbs as long as the hind. Scapulae dilated distally. Pubes not constricted.

Upper Jurassic. Cetiosaurus Owen (Cardiodon Owen), England.

Lower Cretaceous (Morrison). Haplacanthosaurus Hatcher, Brachiosaurus Riggs, Rocky Mts. Gigantosaurus Fraas (non Seeley), (? Brachiosaurus Riggs), South Africa. Pelorosaurus Mantell, Europe, Madagascar.

. Spines of dorsal vertebrae furcate. Front limbs distinctly shorter than hind. Scapulae distally expanded. Ischia slender.

Lower Cretaceous. Camarasaurus Cope (Morosaurus Marsh), Pleurocoelus Marsh, North America. Titanosaurus Lydekker, Europe, Madagascar, India.

Upper Cretaceous. Titanosaurus Lydekker, France, Patagonia.

. Spines of presacral vertebrae furcate. Front legs much shorter than hind. Scapulae narrow distally. Ischia expanded at extremity.

Lower Cretaceous (Morrison). Atlantosaurus Marsh, Apatosaurus Marsh (Brontosaurus Marsh), Amphicoelias Cope, Rocky Mts.

. Spines of presacral vertebrae furcate. Front legs shorter than hind. Teeth slender, confined to anterior part of jaws. External nares near top of skull, remote from extremity. Ischia not expanded distally, the pubes constricted in middle. More slender sauropods.

Lower Cretaceous (Morrison). Diplodocus Marsh, Rocky Mts.


 * ? Jurassic. Dystrophaeus Cope, Rocky Mts.

Upper Jura and Wealden. Bothriospondylus Mantell, Chondrosteus Owen, Chondrosteosaurus Owen, Eucamerotus Hulke, Ischyrosaurus