24 
WALL AND FLOOR CASES, LEFT, AND FLOOR 
CASE, RIGHT. — Triassic fossils. Many types of the Carbonif- 
erous Age continue to be prominent. Equisetum, belonging to 
the family of Equisetse, or “Horsetails'" of the present day, and 
Pterophyllum, of the order of Cycads, were most prominent 
among the land plants, and are illustrated by many specimens. 
Among the Lamellibranchs, the modern genus of Modiola is in- 
troduced. Ceratites represents the Orthoceras of early times from 
which it will be seen to differ in being coiled, and in having a 
more complex suture. 
Jurassic Fossils. — Among plants, Cycads are illustrated by 
several specimens of Cycadoidea, Among invertebrates the 
beautiful Crinoid Pentacrinus is especially noteworthy. Other 
Echinoderms are Cidaris, H emicidaris, Pygaster and Clypeaster, 
the two latter being allied to Clypcus or “sand dollar"’ of the pres- 
ent day. 
Brachiopods, mostly of the sloping shoulder type, are illus- 
trated by the genera Terebratula and Rhynchonella. Among bi- 
valve mollusks the introduction of the modern gtnus oi Ostrea 
or oyster, is notable. 
Tne remainder of the hall is devoted to specimens illustrat- 
ing Dinosaurs, the largest land reptiles the world has ever known. 
Most of the specimens shown were collected by special expedi- 
tions sent by the Museum for the purpose to Wyoming and Colo- 
rado. The specimens include nearly complete fore and hind limbs, 
series of vertebrae, shoulder blades, ribs and numerous limb 
bones of Dinosaurs. The genera represented are Brontosaurus, 
Morosaurus, Claosaurus and others. Perhaps the most im- 
portant specimen is a continuous series of vertebrae from the 
neck dov/nward of an individual Brontosaur. Ribs, pelvis and 
one femur of the same individual are also shown. The vertebrae 
alone aggregate thirty feet in length, and single ones have a 
height of three feet. A femur and humerus of another individual 
Dinosaur are shown, which are the largest bones of this kind 
yet known. Each is six feet eight inches in length, and the 
femur has a weight of about 700 pounds. Mounted fore and hind 
limbs, the latter partially restored (west wall), also give an idea 
of the size and structure of the Dinosaurs. 
FLOOR OF HALL. — Restoration of Hadrosaurus from the 
Upper Cretaceous of New Jersey. This was a huge land reptile. 
