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Blastoids - Two Pentremites in Matrix Chesterian Zone of the Bangor Limestone Formation in northern Alabama Mississippian Period (ca 325,000,000 years old) Blastoids (class Blastoidea) are an extinct type of stemmed echinoderm.[1] Often called sea buds, blastoid fossils look like small hickory nuts. They first appear, along with many other echinoderm classes, in the Ordovician period, and reached their greatest diversity in the Mississippian subperiod of the Carboniferous period. However, blastoids may have originated in the Cambrian. Blastoids persisted until their extinction at the end of Permian, about 250 million years ago. Although never as diverse as their contemporary relatives, the crinoids, blastoids are common fossils, especially in many Mississippian-age rocks. Pentremites is an extinct genus of blastoid echinoderm belonging to the family Pentremitidae. These echinoderms averaged a height of about 11 centimetres (4.3 in)but occasionally ranged up to about 3 times that size. They, like other blastoids, superficially resemble their distant relatives, the crinoids or sea lilies, having a near-idential lifestyle living on the sea floor attached by a stalk. They trapped food floating in the currents by means of tentacle-like appendages. Pentremites species lived in the early to middle Carboniferous, from 360.7 to 314.6 Ma. Its fossils are known from North America. Kingdom: Animalia Phylum: Echinodermata Class: †Blastoidea Order: †Spiraculata Family: †Pentremitidae Genus: †Pentremites

Regispongia Sponge fossils Bangor Limestone Formation in north Alabama Mississippian Period (ca 325,0000,000 yrs old) Sponges, the members of the phylum Porifera (meaning "pore bearer"), are the basalmost clade of animals, as sister of the diploblasts. They are multicellular parazoan organisms that have bodies full of pores and channels allowing water to circulate through them, consisting of jelly-like mesohyl sandwiched between two thin layers of cells. Sponges have unspecialized cells that can transform into other types and that often migrate between the main cell layers and the mesohyl in the process. Sponges do not have nervous, digestive or circulatory systems. Instead, most rely on maintaining a constant water flow through their bodies to obtain food and oxygen and to remove wastes. Kingdom: Animalia Phylum: Porifera Class: Calcarea Order: Heteractinida Family: Wewokellidae Genus: Regispongia

Sphenothallus - a Medusozoa fossil Chesterian Zone of the Bangor Limestone Formation in northern Alabama Mississippian Period (ca 325,0000,000 yrs old) Medusozoa is a clade in the phylum Cnidaria, and is often considered a subphylum. It includes the classes Hydrozoa, Scyphozoa, Staurozoa and Cubozoa. Not all Medusozoa are jellyfish. Sphenothallus is a problematic extinct genus lately attributed to the conulariids. It was widespread in shallow marine environments during the Paleozoic. Sphenothallus is represented in the Cambrian period in the Kaili biota and the Mount Stephen trilobite beds, where it co-occurs with the similar organisms Cambrorhythium and Byronia. It is known in younger strata in Canada and the USA, surviving at least until the Mississippian. Sphenothallus lived in groups as an opportunist in environments from hardgrounds to soft mud, even if depleted in oxygen. It probably dispersed via larvae. Kingdom: Animalia Phylum: Cnidaria Class: Scyphozoa Order: Conulariida Genus: Sphenothallus

Sphenothallus - a Medusozoa fossil Chesterian Zone of the Bangor Limestone Formation in northern Alabama Mississippian Period (ca 325,0000,000 yrs old) Medusozoa is a clade in the phylum Cnidaria, and is often considered a subphylum. It includes the classes Hydrozoa, Scyphozoa, Staurozoa and Cubozoa. Not all Medusozoa are jellyfish. Sphenothallus is a problematic extinct genus lately attributed to the conulariids. It was widespread in shallow marine environments during the Paleozoic. Sphenothallus is represented in the Cambrian period in the Kaili biota and the Mount Stephen trilobite beds, where it co-occurs with the similar organisms Cambrorhythium and Byronia. It is known in younger strata in Canada and the USA, surviving at least until the Mississippian. Sphenothallus lived in groups as an opportunist in environments from hardgrounds to soft mud, even if depleted in oxygen. It probably dispersed via larvae. Kingdom: Animalia Phylum: Cnidaria Class: Scyphozoa Order: Conulariida Genus: Sphenothallus

Spyroceras Cephalopod in Matrix Chesterian Zone of the Bangor Limestone Formation in northern Alabama Mississippian Period (ca 325,000,000 years old) Spyroceras is a genus of pseudorthocerids from the Devonian of North America and Europe, defined by Hyatt in 1884. Pseudorthocerids are a kind of orthocertaoid, a taxonomic group within the Nautiloidea. Spyroceras had annulated orthocones with straight transverse sutures, transverse or slightly oblique surface annulations, and faintly cyrtoconic apeces Surface ornamentation varies but longitudinal lirae are conspicuous from earliest stage. The siphuncle was central or slightly offset ventrally, and composed of expanded segments typical of the Pseudorthocerida. Cameral and siphonal deposits developed later than in most pseudorthocerids and are thus confined to the apical portion of the phragmocone. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Order: Pseudorthocerida Family: Spyroceratidae Genus: Spyroceras

Archimedes Bryzoan in Matrix Bangor Limestone Formation, North Alabama Mississippian Period c 325,000,000 years ago Archimedes is a genus of bryozoans belonging to the family Fenestellidae. The first use of the term "Archimedes" in relation to this genus was in 1838. This genus of bryozoans is named Archimedes because of its corkscrew shape, in analogy to the Archimedes' screw, a type of water pump which inspired modern ship propellers. These forms are pretty common as fossils but they have been extinct since the Permian. Archimedes is a genus of fenestrate bryozoans with a calcified skeleton of a delicate spiral-shaped mesh that was thickened near the axis into a massive corkscrew-shaped central structure. The most common remains are fragments of the mesh that are detached from the central structure, and these may not be identified other than by association with the "corkscrews", that are fairly common. Specimens in which the mesh remains attached to the central structure are rare. Like other bryozoans, Archimedes forms colonies, and like other fenestrates, the individuals (or zooids) lived on one side of the mesh, and can be recognized for the two rows of equally distanced rimmed pores. Inside the branches, neighbouring individuals were in contact through small canals. Bryozoans are stationary epifaunal suspension feeders. The majority of fossils of this genus are distributed throughout Europe and North America, but they have also been found in sediments of Afghanistan, Canada, Russia, and Australia. Kingdom: Animalia Phylum: Bryozoa Class: Stenolaemata Order: †Fenestrida Family: †Fenestellidae Genus: †Archimedes

Crinoid Spine in matrix - with Archimedes Bryzoan fronds on background matrix Chesterian Zone of the Bangor Limestone Formation in northern Alabama Mississippian Period ca 325,000,000 yrs old A matrix with a Crinoid Spine. Crinoids are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). The name comes from the Greek word krinon, "a lily", and eidos, "form". They live in both shallow water and in depths as great as 9,000 meters (30,000 ft). Those crinoids which in their adult form are attached to the sea bottom by a stalk are commonly called sea lilies. The unstalked forms are called feather stars or comatulids. Crinoids are characterised by a mouth on the top surface that is surrounded by feeding arms. They have a U-shaped gut, and their anus is located next to the mouth. Although the basic echinoderm pattern of fivefold symmetry can be recognised, most crinoids have many more than five arms. Crinoids usually have a stem used to attach themselves to a substrate, but many live attached only as juveniles and become free-swimming as adults. There are only about 600 extant crinoid species, but they were much more abundant and diverse in the past. Some thick limestone beds dating to the mid- to late-Paleozoic are almost entirely made up of disarticulated crinoid fragments. Kingdom: Animalia Phylum: Echinodermata Class: Cridoidea