rossii. \i:i{'n:iii{.iri:s what tiiky teach lM7 



To the cast is tlir 'I'ci-I iary Maimnal Hall show iiii;- the cv dIiiI ioii ol' tin- 

 diHVri'iit races of iiiodcrii (iua(lr\ii>c(ls diiriiiu the Aj^^c of Maiiiinals, before 

 man luul emerj^ed from the ohseurity of his pre-liiiinaii existence. Here 

 in successi\e alco\('s arc i)al:contolo,tiical " (locuiiiciits" which illnstrate 

 the past history of the (litl'crcnl kinds of modern mammals, as inlci pretcd 

 and explained hy lahcls and (ha^n-ains. 



By far the most complete of these exhibits is the alco\'e showing tlic 

 Ancestry of the Horse. In other alcoves are illustrations of the ii;eolo^nc 

 history of the camel and other rnminants, of rhinocero.ses, tapirs and 

 carni\-ora. and at the farther end are shown such ej)isodes in the Tertiary 

 history of North .\mcrica as the rise and fall of the l"nit(tihirts and Tifaiio- 

 ihiri.'i, dynasties of extinct j^iant races which ha\e left no living,' descendants. 

 But in a broad way the Tertiary Mammal Hall shows the c\(>lution of the 

 higher quadrupeds, the building up of the animal world of to-day. 



In the Dinosaur Hall we pass into an older world. As in a museum of 

 antiquities we may pass from the halls devoted to the records of the up- 

 building of our modern civilization into those displaying the relics of an 

 older civilization upon whose ruins it is built, so here we pass from the 

 Age of Mammals into the Age of Reptiles, the era of the dinosaurs — gigantic 

 extinct reptiles which were the dominant land animals of that far distant 

 time. They are but remotely related to the living lizards, crocodiles, snakes 

 and turtles, poor and unassuming cousins who have survived the downfall 

 of the giant reptilian lords of the Mesozoic world, and continue even to-day 

 to play their modest part in the economy of nature. The unfamiliar and 

 bizarre proportions and often gigantic size of these Dinosaurs make them 

 the most interesting and impressive of all extinct animals. As yet, their 

 history is imperfectly known, and neither the materials nor the space 

 allotted for their display permit us to show the successive stages in the 

 evolution of the different dinosaurian races. In the far corner of the 

 Dinosaur Hall are the records, still less complete, of a more ancient period, 

 the Age of Amphibians, which precedefl the .\gc of Reptiles; and in the 

 small southeast Tower Hall are the relics of the Age of Fishes which in turn 

 precedes the Age of Amphibians. 



With the building of the projected extensions of this wing of the Museum 

 the space allotted to these older periods of earth history will be 

 expanded, so that the visitor will see displayed in successive halls the 

 records of the Age of Fishes, the Age of Amphibians and Coal plants, the 

 earlier and later periwls of Dinosaur supremacy, and then, passing through 

 the Evolution of the Mammals, will finally reach the Age of Man in the 

 central hall. The materials for filling these successive halls are rapidly 

 accumulating through the efforts of successive expeditions financed by the 

 President and Trustees of the Museum. 



