Brachiopods are shelled invertebrate that look somewhat like bivalved molluscs. However, the animal living in the shell is a filter feeder that collects food with a special organ called a lophopore (bryzozoa also have lophophores).

Bryozoans, sometimes referred to as "moss animals," are a type of simple colonial animal that mostly lives in marine environments (a few inhabit freshwater). Bryozoans feed by means of a lophophore, a small ring of tentacles covered with tiny cilia that are used to filter food from the water. Bryozoan colonies are protected with a covering of organic materials or calcium carbonate. Some calcium carbonate forms may be found as fossils in the Cretaceous strata near the C & D Canal.

While sampling the lower Miocene Calvert Formation at the Pollack Farm Site, 30 fossil fish taxa were collected, consisting of 24 cartilaginous and 6 osteichthyes fishes. The fossils found in the lower Miocene bed have similar characteristics to an equally aged Formation in southern Delaware suggesting deposition occured in a subtropical, shallow-water, near shore environment.

The majority of Arthropods recovered at the lower Miocene bed are from various species of crustaceans (lobsters, shrimp, barnacles). Fossils from crustaceans often consist of small body parts such as claws. However, crustaceans such as ghost shrimp (callichirus) tend to construct burrows that resemble lumpy tubes called Ophiomorpha. These corn-stalked resembling tunnels, are created from mud and depository waste to form burrows in which the creatures reside. In comparison to claws and pincher fossils, "trace fossils", such as Ophiomorpha tubes, are often commonly found in greater number than that of various body parts.

Clams, mussels, oysters, and scallops are members to the class Bivalvia (or Pelecypodia). Bivalves have two shells, connected by a flexible ligament, which encase and shield the soft vulnerable parts of the creature. All 15,000 known species of bivalves are aquatic in nature, with close to 80% being marine (saltwater environments).

The Class Gastropoda includes the groups pertaining to snails and slugs. The majority of gastropods have a single, usually spirally, coiled shell into which the body can be withdrawn. The shell of these creatures is often what is recovered in a fossil dig. Gastropods are by far the largest class of molluscs, comprising over 80% of all molluscs.

Located in Kent County, Delaware, the Pollack Farm Site was a surprise to many to contain numerous fossils. The fossils discovered range from a simple Arthropod, small insect, to large vertebrates, such as sharks. In 1991, while Delaware Geological Survey staff collected earth minerals during a highway construction, they came across an upper shell bed full of molluscan fossils. As digging continued numerous fossils of various species and phylum were found.

Cnidarians are soft-bodied animals that include corals, jellyfish, and sea anemones. These soft-bodied animals have saclike digestive cavities and tentacles containing rows or stinging cells used for defense and capture of food. Many secrete calcium carbonate to support and partly enclose the soft parts; the most familiar of these are corals. The only members of the phylum found at the Canal are solitary corals. One of these corals, Micrabacia, may be the most common fossil found. Another common fossil found there, a solitary horn-shaped coral, has been given different names by different authors.

Phylum Porifera is a group of simple animals that includes the sponges. Porifera have no internal organs, nervous tissue, circulatory system, or digestive systems, making them the most primitive of the multi-cellular animals. To support and protect their soft bodies, sponges produce skeletons of calcium carbonate, silica, or a soft organic material called spongin. The most common fossil sponge in the Cretaceous sediments of Delaware is the genus Cliona. Cliona sponges lived on rocks and shells of the seafloor and commonly bored holes in these objects, in which it lived. To obtain food, the sponges filtered the water around them as it passed through tiny pores located on their outer walls. The sponge is common in the Mount Laurel Formation along the Canal.

Protozoans are one-celled organisms that include the amoeba. One group of protozoans, the Foraminifera ("forams"), are among the most common fossils found in the Cretaceous of Delaware -- but are hard to study without a microscope. Forams build a hard outer covering -- some by secreting calcium carbonate or opaline silica, some by cementing sand grains -- in order to provide support and protection. The resulting many-chambered shells, which are commonly called "tests," are the parts preserved as fossils. Some are very simple, and others are very ornate.

These pages describes many of the types of fossils that are known from the Cretaceous deposits of Delaware. It includes pictures and drawings of many of the fossils. It also provides a checklist of Delaware's Cretaceous as well as some maps that show collecting sites and the geology of the area.

Delaware offers a few sites for fossil collectors, and the Chesapeake and Delaware Canal and the Pollack Farm are the best. Other locations throughout the state also offer good hunting grounds for fossil collectors. Just south of Dagsboro, where Route 113 crosses Pepper Creek, the collector can find young (less than 2 million year old) marine fossils from the Pleistocene Epoch. At the state sand and gravel pit just south of Middletown on Route 896, plant impressions from the Pleistocene may be found.

If you think you may have found a Delaware dinosaur or any unusual fossil, the scientists at the Delaware Geological Survey at the University of Delaware, Newark campus would like to see it. It could provide important information on the geologic history of the First State.