636 SIM OY OPUERS ITH ON GSIMOGI OV ANI 
been referred by Marsh to these genera have been taken from 
the Potomac Beds of Maryland. 
Le@laps was one of the same type of Dinosaurs as those 
already described It is from the upper Cretaceous of New 
Jersey and Montana. The animal had a length of about fifteen 
feet. 
The European forms presented scarcely less varied types 
than the American forms, but the bones are less well preserved 
and the skeletons consequently less well known. Prominent 
ones are Megalosaurus and Streptospondylus. The first, from the 
Jurassic of England and many parts of the continent, is also 
known from the Jurassic beds of Colorado and from the Creta- 
ceous of the East Indies. It was one of the largest of the Zhe- 
ropoda, the femur being over a meter in length. 
Aristosuchus, from the Wealden of England, is somewhat 
similar to Celurus, having similar cavernous vertebre and light 
limb bones 
Tanystrophaeus, from the Muschelkalk of Bayreuth, is remark- 
able for the extremely elongated cervical and caudal vertebre. 
They are eight or ten times as long as they are broal, and are 
hollow as in Celurus. The same form is known from the Trias- 
sic rocks of New Mexico. 
SAUROPODA (Cetiosauria).— Brain case completely ossified 
in front; a well developed alisphenoid; no epipterygoid (colu- 
mella) ; premaxillaries not excluding the maxillaries from the 
nasal opening; jugal and quadrate forming a continuation of the 
posterior border of the maxillary in the same plane; quadrato- 
jugal in connection with the maxillary: quadrate directed for- 
ward; mandible without predentary bone; dentary without 
coronoid process; sacral ribs attached to a single vertebra; 
neural canal much expanded in the sacrum; limb bones without 
medullary canal; the fore and hind limbs nearly of the same 
size; feet plantigrade; the termination of the toes in nails or 
hoofs rather than in claws. 
The order is practically unknown in Triassic time, but in the 
