Finger Lakes
Geology Websites


-Introduction
-Brief Summary
-Formation of the _Finger Lakes
-Ithaca is Gorges
-Rocks of the _Finger Lakes
-Fossils in Ithaca
State Parks
-Treman
-Buttermilk Falls
-Taughannock
-Watkins Glen
 

Fossils of the Ithaca area

Fossils are abundant in the Ithaca area, and easy to collect. All date from the Ordovician to the Late Devonian Period, and all were buried in mud and sand that accumulated in a shallow sea between 450 and 360 million years ago. Life in this warm ancient sea was abundant and diverse, just as in warm seas today, but the kinds of animals were very different. Fossils of many groups of organisms can be found, including more than 400 species; following is a list of only some of the more common types.

Brachiopods are the most common fossils in the area. Brachiopods have two shells, and look superficially like clams, but the internal anatomy of brachiopods reveals that they are actually very different kinds of animals. You can tell a brachiopod because they have symmetry across the shells instead of between the shells, as do clams. Brachiopods are still alive in oceans today but are much less common than they once were.

Clams (bivalves) are mollusks with two shells. Clams were common in the Devonian, but not as abundant or diverse as they are now on ocean beaches.



Altrypa spinosa, a Devonian fossil of the Finger Lakes region


Trilobite
Illustrations from
Devonian Paleontology
(Linsley, 1994).

Trilobites are an extinct group of animals related to living horseshoe crabs and lobsters. They may look a bit like pill bugs or insects in that they have segmented bodies and sometimes compound eyes. Two kinds of trilobites are frequently found in rocks around Ithaca, and one is especially common. It is rare to find whole trilobites because most fossils are of the broken molted skins of growing trilobites.

Corals come in two kinds among the Devonian fossils of Ithaca: rugose or "horn" corals, and tabulate or "honeycomb" corals. Both of these kinds of corals are extinct, but they resemble modern corals in some ways.

Crinoids (sometimes called "sea lilies") are not plants but are relatives of starfish and sea urchins. They have a multi-armed head on a long, flexible stalk made of many discs. The discs are often preserved as fossils.

Cephalopods are mollusks and today include squids, octopus and the chambered nautilus. Fossils of two kinds of cephalopods can be found in the rocks around Ithaca. Both have straight or coiled shells divided into separate chambers. Nautiloids have simple curved walls separating these chambers; ammonoids have more complex walls.


Crinoid
stems


Ammonoid

Illustrations by Paul Krohn.

Fossils are present in varying abundance in almost all rocks in the Finger Lakes region. The rocks that are richest in fossils are frequently gray shales or fine-grained sandstone, or limestone. It is easiest to collect fossils from shales, because these rocks are rather soft and break apart easily into layers. You will find a greater variety of fossils if you collect from a variety of rock types and locations. You are most likely to find rocks abundantly exposed (that is, not covered by soil or pavement) along stream beds, in quarries, or at road cuts.



If you want to know more about the fossils in the Finger Lakes area, make sure to visit PRI and the Museum of the Earth, which is currently under construction. At PRI you can see fossils on display and learn more about the history of the earth. You should also check out PRI's array of educational resources, including Ithaca Is Gorges, The Teacher-Friendly Guide to the Geology of the Northeastern U.S. (a good source for anyone interested in area geology), and Lasting Impressions: A Guide to Understanding Fossils in the Northeastern United States. These materials are great resources for anyone wanting to collect and hunt for fossils on their own. The above materials and many other books, clothing, and toys can be found online at The Museum Store or by visiting PRI.

 

Previous Page | Next Page

 
The Paleontological Research Institution
1259 Trumansburg Road
Ithaca, NY 14850 phone: 607-273-6623 fax: 607-273-6620
Questions about the Website? Tell us!