Mississippian Period Foraminifera

This fossil is a foraminifera from the Salem Limestone of Indiana.  It was found in Washington County, Indiana.  The little creature existed in the Mississippian Period.  I believe this is my first microfossil posted since I tend not to look for these animals.  After finding a binocular microscope to use, I searched through some cleaned sand that my friend Herb gave me.  With a vague idea of looking for a multi-segmented bubbly looking rolled up worm shape, I found about nine fossils in about 45 minutes.

Reading about this limestone layer ahead of time gave me the impression that it had a lot of micro fossils.  It lived up to its billing with fragments of bryozoans, small snail shells, spine looking shapes, and crinoid discs were among the fossils I visually encountered.  According to my research, the fossils pictured might be an Endothryra baileyi or Globoendothyra baileyi.

The pictures were taken through the microscope viewing lens using a 4 megapixel Kodak camera set to macro mode.  Forgive the picture quality.  I believe the microscope magnification was set between 20x-30x.

The last three pictures were taken at the Indiana State Museum in Indianapolis.  They are specifically from the Mississippian Period display which is describing fossils in the Salem Limestone.

 

A model of one of these micro-sized fossils.

 

Learn more about these tiny creatures at the German website www.foraminifera.eu run by Michael Hesemann.  If you can, help him out by sending fossil samples for him to photograph and document.

Recent Devonian Fossil Finds

The snow has pretty much melted and it is above freezing so time for a quick jaunt to look for fossils. The Devonian corals are always good to find and some of them made an appearance. This first set of fossils though are crinoid stems with branch remanents. I sometimes wonder if they are holdfasts of some sort.

 

 

Here is a fossil of a brachiopod that might be a Brevispirifer.

 

 These next three images are of the Aulacophyllum horn coral that has a diamond like shape.  Found in the Jeffersonville Limestone of Jefferson County Kentucky.

 

 

 

Quest for a Horn Coral

I continue to search for the elusive Bordenia knappi (Hall, 1882) horn coral.  It is challenging to understand some of the paleontology literature though.

From the library, I checked out Treatise on Invertebrate Paleontology Editor Curt Teichert, Part F Coelenterata Supplement 1 Rugosa and Tabulata by Dorothy Hill Volume 1, The Geological Society of America, Inc. and The University of Kansas 1981.  Page F147 it says, "Bordenia Greene, 1901, p. 57 [*B.zaphrentiformis] Solitary, irregular ceratoid or trochoid with talon, or weak colonial, with peripheral offsets; major septa long but amplexoid; minor septa short; tabulae complete, horizontal, with downturned edges; no dissepiments."  It then lists it as Mississippian Period found in Indiana and Kentucky.  Whoa!  I think this is a Devonian Period coral.

George K. Greene published Contributions to Indiana Paleontology on page 99 describes Bordenia knappi and with plates 31 figures 4-11.  "Zaphrentis deformis, Hall Twelfth Annual Report of the Indiana Geological Survey, 1882, page 290, plate 20, figure 9-10.
Zaphrentis Knappi, Hall, Thirty-fifth Annual Report of the State of New York, page 438, 1884.
As the descriptions for both species are the same, I prefer the specific name Knappi, as this was intended as a compliment by Prof. Hall, to his old friend, Dr. James Knapp, of Louisville, Ky.
Corallum simple, or composite, and sometime growing socially, two or more together, with a broad scar at the point of attachment.  Gradually, or sometimes more rapidly, expanding in diameter to the calix.  Height varying in different individuals, from fifteen to forty millimeters.  Diameter of calix, from ten to twenty-five millimeters.  Depth, five to ten millimeters, with a smooth space in the center of the calix, occupied by the tabulae, from ten to twelve millimeters in diameter.  Number of lamellae, from thirty to thirty-two, in the circumference of a calix, twenty-five millimeters in diameter.  When well preserved they are unequal in size, and sharp at the margin, gradually descends to to the smooth space in the center of the calix, but does not extend on the side of the coral.  Exterior with numerous strong rounded annulations and wrinkles, caused by periodical growth.
Found in the Upper Devonian (Hamilton group) at Charlestown, and in the strippings above the different cement quarries, throughout Clark County, Indiana, now in my collection."

E.C. Stumm's book Corals of the Silurian and Devonian Corals of the Falls of the Ohio describes it on page 46 as "Corallum simple, small, highly distorted, with thick epitheca and one or several talons of attachment.  Average length about 3 cm, average calyx diameter 1.5 cm.  Calyx very shallow.  Septa about 25-30, of equal size, extending more than half distance to axis.  No distinct fosula. Tabulae complete, about 2 mm apart.  No dissepiments."