Report of the President 73 



from the Tyrannosaurus, a long-necked, slenderly proportioned? 

 active animal, with small head and no teeth. A fine panel 

 skeleton of this rare type has been completed. 



The skeleton of the Duck-billed Dinosaur Corythosaurus 

 has been completed and installed in the Dinosaur Hall. In 

 this specimen a great part of the skin of body, limbs and tail 

 was preserved on both right and left sides, but the crushing 

 of the rocks had flattened the specimen until in some places 

 it was hardly thicker than paper, while in other parts it was 

 very thick, heavy and fragile. To preserve and prepare this 

 specimen without damage and exhibit both sides of the animal 

 constituted a difficult and tedious piece of preparation work, 

 involving a network of steel rods and wires concealed within 

 and below the specimen. Besides being the type of a new 

 genus and species, it shows the skin, the ossified tendons and 

 even some traces of the muscles. 



In the Hall of the Age of Man, the entire exhibit of fossil 

 Proboscidea has been rearranged and reinstalled, much new 

 material being added. Among these additions are: (1) 

 remains of a frozen mammoth from northwestern Alaska found 

 by Mr. L. S. Quackenbush in 1908; (2) series of teeth and 

 jaws of fossil elephants and mastodons to illustrate their 

 distribution, phylogeny, etc. ; (3) male and female mastodon 

 and elephant skulls, jaws, etc. ; (4) jaws and teeth of Tertiary 

 proboscideans, illustrating the principal known types; (5) 

 skulls and jaws illustrating the evolution of the mastodon 

 {Moeritherium, Palceomastodon, Trilophodon, JDibelodon, Mas- 

 todon) . 



On the south side of the same hall, considerable additions 

 and rearrangements are in progress among the fossil mammals 

 of South America. 



Two mounted skeletons have been added to the series in 

 the Tertiary Mammal Hall. One is the large extinct wolf 

 Cants dirus from the asphalt beds at La Brea, the other the 

 extinct Pampean deer of South America, Brachyceros pampozus. 

 The reinstallation of the exhibits on the' south side of the 

 Dinosaur Hall is in progress, the new method of panel mount- 

 ing allowing large additions to the exhibits, besides showing 

 each specimen more effectively. 



