j. Alabaster. 
3. Economic Minerals. 
a. Fluor Spar. 
b. Strontium bearing minerals. 
c. Abrasives. 
d. Asbestus. 
e. Alkalies. 
f. Phosphates. 
g. Limestone. 
h. Gypsum. 
i. Salts. 
E. Hall 38. Historical Geology. 
This hall is arranged to illustrate the forms of life 
which have characterized the successive stages of the 
earth’s history. 
(South to North) 
1. Methods of fossilization. 
2. Comparisons of ancient and modern plants 
and animals. 
3. Fossils of the Age of Invertebrates. 
a. Early forms. 
Trilobites, Cephalopods, Brachiopods, etc. 
b. Later forms. (Niagara Period). 
Crinoids, Sponges, Crustaceans, etc. 
4. Fossils of the Age of Fishes. 
5. Fossils of the Age of Coal Plants. 
a. Stump of Fossil Tree. 
b. Ferns, Invertebrates, Fishes, etc. 
6. Fossils of the Age of Reptiles. 
a. Dinosaurs. 
b. Sea Lizards. 
c. Great Horned Lizard (Dinosaur). 
d. Swimming Reptiles. 
e. Flying Reptiles. 
7. Fossils of the Age of Mammals. 
a. Titanotheres. 
b. Fossil Elephant. 
c. Fossil Shark. 
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