5-! 
landing of the stair leading to the Hall, and others at the south end 
of the room. Still others of smaller species may be seen in the 
Triassic, Case o. These tracks were made by large lizard-like 
animals having the habit of walking on their hind feet. They 
are called Dinosaurs (terrible lizards) and attained immense size. 
There are also fossil Turtles under the Miocene, Case Q, from 
the Upper Missouri, and a cast of a left femur (thigh bone), from 
an immense Marine Lizard, Atlantosaurits, from the Jurassic of 
Colorado, in Case o, Sect. 12. In the European collection there 
are some fine specimens of Ichthyosaurus from the Lyme Regis 
beds of the Lias, in England, Case R, and jaws and teeth of a 
Mosasaurus in Alcove Case 14, and in the case of vertebrates. 
Fig. 41.— REPTILES. 
Fig. 41. — Tcthyosaurus communis, 1-36 of natural size. 
BIRDS. 
In the case to the right of the door, as one enters the room, 
there is a fine series of skeletons of the fossil birds of New Zea- 
land, the Moas. A larger one occupies the middle of the Hall- 
These birds were allied in form and character to the ostrich of 
the present day, but were more completely destitute of wings 
(Apterous). They are found buried in superficial deposits, under 
such circumstances as to lead to the belief that they became 
extinct during the Human period. There are also some bones of 
the Dodo, a large bird of about fifty pounds weight, formerly abund- 
ant on the Island of Mauritius, but which became extinct during 
the early part of the eighteenth century. Also a plaster cast of a 
fossil egg of dipyornis maximus, another large fossil bird from 
Madagascar (Case t). There is also a series of casts of the fossil 
toothed birds from the Cretaceous rocks of the Rocky Mountains, 
so ably described by Prof. O. C. Marsh, by whom they were 
presented, in the Alcove Case 13, under the Cretaceous period. 
