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State Fossils
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Delaware State Fossil
Cretaceous Belemnite
(Belemnitella americana)
Adopted on July 2, 1996.
On July 2, 1996, Cretaceous Belemnite, Belemnitella americana, was named as the official fossil
of Delaware. The Martin Luther King, Jr. Elementary School (Wilmington) third grade Quest students of Kathy Tidball
suggested honoring the ancient and noble belemnite as our State fossil.
State Code
§ 314. State fossil.
The official state fossil is the belemnite. (70 Del. Laws, c. 427, § 1.)
The belemnite was, in essence, a squid with a conical shell. It is an extinct member of the phylum Mollusca,
which includes clams, snails, squids and octopuses. Belemnite fossils can be easily found along the Chesapeake and
Delaware Canal, which is where the Quest Students collected specimens during a field trip.
Belemnite is the common name applied to an extinct order (Belemnoida) of mollusks belonging to the cephalopod
class. Modern cephalopods include the squid, octopus, and pearly Nautilus. The belemnoid animal was most closely
related to the squid as it had an internal shell covered by a leathery skin, tentacles that pointed forward, and
a siphon that expelled water forward thus moving the animal backward by jet propulsion. The internal shell of the
belemnoid was cone-shaped and divided into chambers that were gas-filled for maintaining buoyancy in the sea. The
chambered shell had a blade-like forward extension that is seldom preserved as a fossil. The most common fossilized
part of the internal shell is called the "guard" or "cigar" consisting of a massive, generally brown-colored, subcylindrical
structure called the rostrum that encloses the chambered shell and extends to the rear where it tapers to a conical
apex. The rostrum served as a counter-weight to the buoyancy provided by the chambered shell and also for protection
of that delicate shell. Belemnoids reached their greatest abundance and diversity during the Jurassic and Cretaceous
periods.
Belemnites have been found abundantly in the exposures of the Mount Laurel Formation along the banks of the Chesapeake
and Delaware Canal in Delaware, east of St. Georges. The fine-grained sands and silts of the Mount Laurel were deposited
in a shallow sea during the Late Cretaceous time around 70 million years ago. The fossil belemnite species found
here is Belemnitella americana.
Sometimes, almost complete belemnite guards can be found, similar in size and shape to a pencil, pointed
at one end, but flaring at the other end (if preserved) and partly hollow in the center where the chambered shell
was located. Often, only rod-like broken sections of the brown rostrum are found.
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State Fossils
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Most US states have made a state fossil designation, in many
cases during the 1980s. It is common to designate one species in which fossilization has
occurred, rather than a single specimen, or a category of fossils not limited to a single
species.
Some states that lack a "state fossil" have nevertheless singled out a fossil for formal
designation such as a state dinosaur, rock, gem or stone.
fossil (fŏs'əl)
n.
1. A remnant or trace of an organism of a past geologic age, such as a skeleton or
leaf imprint, embedded and preserved in the earth's crust.
2. One, such as a rigid theory, that is outdated or antiquated.
adj.
1. Characteristic of or having the nature of a fossil.
2. Being or similar to a fossil.
3. Belonging to the past; antiquated.
[From Latin fossilis, dug up, from fossus, past participle of fodere, to dig.]
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