
GEOLOGY AND INVERTEBRATE PALAUONTOLOGY SY 
beginning at the northeast corner of the hall with the archzean rocks, which 
are the lowest and oldest of all and contain no fossils, ad- 
Series to vancing regularly southward along the east side through the 
Show ; ag hee ; 
Historical Cambrian, Ordovician, Silurian and Devonian systems, passing 
Geology to the west side of the hall in the Devonian and continuing 
through the Carbonifercus, Jurassic, Triassic, Cretaceous 
and Tertiary. Thus far the specimens are from American localities, but 
the northwest quarter of the hall is devoted to a synoptic series of European 
fossils. The cases in the middle of the hall contain overflow material from 
the sides. The American series is subdivided into geographical provinces, 
the fossils from New York State and other eastern regions being placed first 
and then the material from the Central West and beyond. Under the 
geographical subdivision the species are arranged according to their position 
in the seale of life — that is, following a biological classification, the lower or 
sunpler forms being placed first. The diamond-shaped bits of emerald 
green paper attached to some of the specimens indicate those, more than 
8,000 in number, known as “types” or “figured specimens,’ which have 
been used by James Hall, R. P. Whitfield and others in the original descrip- 
tion and naming of species or in their elucidation. 
The upper shelves of the wall cases contain particularly large or striking 
specimens of fossils, or blocks of rock illustrating the geological features of 
the horizons in which the fossils occur. 
Two floor cases in the middle of the hall at the north end contain a 
series of rock specimens showing the geology of Manhattan 
Geology of = JsJand and a very complete collection of the minerals found 
Manhattan . .. Y a . ae sae hes 
ead in New York City and immediate vicinity belonging to the 
New York Mineralogical Club. 
Attention may be called also to the collection of Michigan copper ores, 
orbicular granites and diorites from several parts of the world, fossil crinoids 
from Waldron and Crawfordsville, Indiana, fossil corals frcem the Devonian 
reefs near Louisville, Kentucky, fossil crinoids and an immense clamlike 
shell from the Cretaceous of Nebraska, fossil plants from Tertiary beds 
at Florissant, Colorado. The windows contain some colored transparencies 
from photographs of interesting scenery in the West. 
I 
[Return to the Hall of Mastodons and Mammoths and turning to the right 
enter the West Corridor or Gem Hall.] 
