Wooster’s Fossil of the Week: A stromatoporoid (Middle Devonian of central Ohio)

February 17th, 2017

Stromatoporoids are very common fossils in the Silurian and Devonian of Ohio and Indiana, especially in carbonate rocks like the Columbus Limestone (from which the above specimen was collected). Wooster geologists encountered them frequently on our Estonia expeditions in the last few years, and we worked with at least their functional equivalents in the Jurassic of Israel (Wilson et al., 2008).

For their abundance, though, stromatoporoids still are a bit mysterious. We know for sure that they were marine animals of some kind, and they formed reefs in clear, warm seas rich in calcium carbonate (DaSilva et al., 2011). Because of this tropical habit, early workers believed they were some kind of coral, but now most paleontologists believe they were sponges. Stromatoporoids appear in the Ordovician and are abundant into the Early Carboniferous. The group seems to disappear until the Mesozoic, when they again become common with the same form and life habits lasting until extinction in the Late Cretaceous (Stearn et al., 1999).

The typical stromatoporoid has a thick skeleton of calcite with horizontal laminae, vertical pillars, mounds on the upper surface called mamelons, and dendritic canals called astrorhizae shallowly inscribed on the mamelons. These astrorhizae are the key to deciphering what the stromatoproids. They are very similar to those on modern hard sponges called sclerosponges. Stromatoporoids appear to be a kind of sclerosponge with a few significant differences (like a calcitic instead of an aragonitic skeleton).

Stromatoporoid anatomy from Boardman et al. (1987).

Top surface of a stromatoporoid from the Columbus Limestone showing the mamelons.

There is considerable debate about whether the Paleozoic stromatoporoids are really ancestral to the Mesozoic versions. There may instead be some kind of evolutionary convergence between two groups of hard sponges. The arguments are usually at the microscopic level!

The stromatoporoids were originally named by Nicholson and Murie in 1878. This gives us a chance to introduce another 19th Century paleontologist whose name we often see on common fossil taxa: Henry Alleyne Nicholson (1844-1899). Nicholson was a biologist and geologist born in England and educated in Germany and Scotland. He was an accomplished writer, authoring several popular textbooks, and a spectacular artist of the natural world. Nicholson taught in many universities in Canada and Great Britain, finally ending his career as Regius Professor of Natural History at the University of Aberdeen.

Henry Alleyne Nicholson (1844-1899) from the University of Aberdeen museum website.


Boardman, R.S., Cheetham, A.H. and Rowell, A.J. 1987. Fossil Invertebrates. Wiley Publishers. 728 pages.

DaSilva, A., Kershaw, S. and Boulvain, F. 2011. Stromatoporoid palaeoecology in the Frasnian (Upper Devonian) Belgian platform, and its applications in interpretation of carbonate platform environments. Palaeontology 54: 883–905.

Nicholson, H.A. and Murie, J. 1878. On the minute structure of Stromatopora and its allies. Linnean Society, Journal of Zoology 14: 187-246.

Stearn, C.W., Webby, B.D., Nestor, H. and Stock, C.W. 1999. Revised classification and terminology of Palaeozoic stromatoporoids. Acta Palaeontologica Polonica 44: 1-70.

Wilson, M.A., Feldman, H.R., Bowen, J.C. and Avni, Y. 2008. A new equatorial, very shallow marine sclerozoan fauna from the Middle Jurassic (late Callovian) of southern Israel. Palaeogeography, Palaeoclimatology, Palaeoecology 263: 24-29.

[Originally published on October 30, 2011]

Wooster’s Fossil of the Week: An atrypid brachiopod from the Devonian of Spain

April 15th, 2016

1 Atrypid dorsal Lr Couvinian M Dev El Pical Leon SpainOur featured fossil this week is another gift from brachiopod enthusiast Clive Champion of England. This fine specimen of Atrypa sp. was collected from the Middle Devonian (Lower Couvinian) exposed at El Pical, Leon, Spain. Atrypa is the emblematic genus of the atrypid brachiopods, which were common in the Devonian around the world. They were also prominent in the Late Ordovician of the Cincinnati region, as seen here and here. We are looking at the dorsal valve in the above view.

2 Atrypid spiraliaThis particular specimen is not notable for its special beauty (it is, after all, exfoliated and a bit misshapen), but for the view it provides of an internal feature: the spiral brachidium, sometimes called the spiralia. This was a ribbon of calcite that supported the lophophore, a tentacular apparatus used in filter-feeding. We see it here because the dorsal valve eroded away, exposing the inside of the shell. Our friends at The Falls of the Ohio have another specimen showing the spiral lophophore of an atrypid.

3 Atrypid ventralThis is a view of the flat ventral valve of our atrypid brachiopod. Inside during life the spiral lophophore would have looked like two springs perpendicular to the floor of this valve.

Thank you again, Clive, for the beautiful and inspiring brachiopods!


Bose, R. 2013. A geometric morphometric approach in assessing paleontological problems in atrypid taxonomy, phylogeny, evolution and ecology, p. 1-9. In: Biodiversity and Evolutionary Ecology of Extinct Organisms. Springer, Berlin and Heidelberg.
Rudwick, M.J.S. 1960. The feeding mechanisms of spire-bearing fossil brachiopods. Geological Magazine 97: 369-383.


Wooster’s Fossil of the Week: A mystery from the Middle Devonian of Ontario, Canada

March 11th, 2016

Hungry Hollow 1This week’s fossil is a strange one. Mr. Darrell Ellis collected the above tiny specimen from the Hungry Hollow Member (Middle Devonian) at the famous Hungry Hollow location near Arkona, Ontario. (He also took this excellent photograph.) In the classic way exploratory paleontology works, he contacted an expert, my friend Olev Vinn at the University of Tartu in Estonia. Olev was puzzled, having never seen anything like it, so he sent the image to me. I was baffled. Darrell next sent me the actual specimen, which I examined an photographed. I could see that it is a calcitic spiral, flattened tube extending from a discoidal holdfast at its proximal end. I then passed images on to another buddy and expert, Paul Taylor at the Natural History Museum in London. The form is new to Paul as well, and he suggested it might be an odd microconchid, a twisty tube-dweller now extinct. That made sense, even if no microconchid like this has ever been described. We know that some microconchids did grow tubes extended upwards (such as Helicoconchus from the Permian of Texas, described earlier in this blog). Since we need to see the microstructure of the calcitic tube to support the hypothesis that this is a microconchid, I then sent the specimen to yet another friend, Michał Zatoń at the University of Silesia in Poland. He will examine the specimen with a scanning electron microscope (SEM). This is citizen science at work. Thank you, Darrell, for donating this specimen to science. It is also a reflection of how small scientific networks exchange ideas, information and specimens — Olev, Paul and Michał have been featured in this blog many times; we are old friends and colleagues with similar interests and diverse skill sets (and equipment!).

Hungry Hollow 2This is a closer view of the top of the spiral. We hope that Michał will be able to see the microstructure of the calcite on these broken surfaces.

Hungry Hollow 3This is the simple holdfast of this specimen. The tube began to grow  upwards very early in its ontogeny.

If you have ever seen a specimen like this before, whole or partial, please let me know in the comments or by email. We have only this one specimen that is clearly “new to science”. Other collectors and paleontologists may have bits of this they did not recognize before.

Again, thank you to Darrell Ellis for his sharp eyes, eagerness to contact experts, and generosity!


Wilson, M.A., Vinn, O. & Yancey, T.E. 2011. A new microconchid tubeworm from the Artinskian (Lower Permian) of central Texas, USA. Acta Palaeontologica Polonica 56: 785-791.

Zatoń, M. & Vinn, O. 2011. Microconchids and the rise of modern encrusting communities. Lethaia 44:5-7.

Zatoń, M., Wilson, M.A. and Vinn, O. 2012. Redescription and neotype designation of the Middle Devonian microconchid (Tentaculita) species ‘Spirorbis’ angulatus Hall, 1861. Journal of Paleontology 86:417-424.


Five-Year Anniversary Edition of Wooster’s Fossil of the Week: A tabulate coral from the Devonian of northwestern Ohio

January 1st, 2016

AuloporaDevonianSilicaShale010211This post of Wooster’s Fossil of the Week marks five years of this feature. If you’re counting, that is 260 entries, with never a week missed. To celebrate, I’m returning to the very first fossil in the series, a beautiful encrusting tabulate coral. The original entry is below, with some updates and added links.

This week’s fossil was collected by Brian Bade of Sullivan, Ohio, and donated to Wooster as part of my hederelloid project.  It is a beautiful specimen of the tabulate coral Aulopora encrusting a brachiopod valve from the Silica Shale (Middle Devonian — about 390 million years old) of northwestern Ohio.  [Update: I now know the species is A. microbuccinata Watkins, 1959.] Auloporid corals are characterized by an encrusting habit, a bifurcating growth pattern, and horn-shaped corallites (individual skeletal containers for the polyps).

What is especially nice about this specimen is that we are looking at a well preserved colony origin.  The corallite marked with the yellow “P” is the protocorallite — the first corallite from which all the others are derived.  You can see that two corallites bud out from the protocorallite 180° from each other.  These two corallites in turn each bud two corallites, but at about 160°.  This pattern continues as the colony develops (a process called astogeny).  The angles of budding begin to vary depending on local obstacles; they never again go below 160°.

The polyps inside the corallites are presumed to have been like other colonial coral polyps.  Each would have had tentacles surrounding a central opening, and all were connecting by soft tissue within the skeleton.  They likely fed on zooplankton in the surrounding seawater.  This type of coral went extinct in the Permian, roughly 260 million years ago.

Again, we thank our amateur geologist friends for such useful donations to the research and educational collections in the Geology Department at Wooster.

Later I began to add information about a notable paleontologist associated with the highlighted fossil. I especially wanted to put a face and brief biography with a name we may often see in our taxonomic pursuits but know little about. We can now add this German gentleman from a previous entry —
August_Goldfuss_1841Aulopora was first described in 1826 by Georg August Goldfuss (1782-1848), a German paleontologist and zoologist. (Goldfuß is the proper spelling, if I can use that fancy Germanic letter.) He earned a PhD from Erlangen in 1804 and later in 1818 assumed a position teaching zoology at the University of Bonn. With Count Georg zu Münster, he wrote Petrefacta Germaniae, an ambitious attempt to catalog all the invertebrate fossils of Germany (but only got through some of the mollusks). The 1841 portrait above is by Adolf Hohneck (1812-1879).

Since the first few entries I began to add a few critical references for the fossils and related stratigraphy. At first these were for me so that I could remember where I got the information used in the text. Later I noted that students and others were finding these entries online and using them as brief introductions to particular taxa. A few references made each entry a starting point for someone else’s paleontological explorations. Here are some added citations for Aulopora


Fenton, M.A. 1937. Species of Aulopora from the Traverse and Hamilton Groups. American Midland Naturalist 18: 115-119.

Fenton, M.A. and Fenton, C.L. 1937. Aulopora: a form-genus of tabulate corals and bryozoans. American Midland Naturalist 18: 109-115.

Goldfuß, G.A. 1826-1844. Petrefacta Germaniae. Tam ea, quae in museo universitatis Regia Borussicae Fridericiae Wilhelmiae Rhenanae servantur, quam alia quaecunque in museis Hoeninghusiano Muensteriano aliisque extant, iconibus et descriptionibus illustrata = Abbildungen und Beschreibungen der Petrefacten Deutschlands und der angränzenden Länder, unter Mitwirkung von Georg Graf zu Münster, Düsseldorf.

Helm, C. 1999. Astogenese von Aulopora cf. enodis Klaamann 1966 (Visby-Mergel, Silur von Gotland). Paläontologische Zeitschrift 73 (3/4): 241–246. [Courtesy of Paul Taylor]

Scrutton, C.T. 1990. Ontogeny and astogeny in Aulopora and its significance, illustrated by a new non‐encrusting species from the Devonian of southwest England. Lethaia 23: 61-75.

Watkins, J.L. 1959. Middle Devonian auloporid corals from the Traverse Group of Michigan. Journal of Paleontology 33: 793-808.

Wooster’s Fossil of the Week: A fragmentary rostroconch from the Middle Devonian of Ohio

November 27th, 2015

1 Hippocardia 1Not all of our featured fossils are particularly beautiful, or even entire, but they are interesting in some way. Above is the broken cross-section of a rostroconch mollusk known as Hippocardia Brown, 1843. It was found somewhere in Ohio by the late Keith Maneese and kindly donated to the department by his widow Cameron Maneese. From its preservation and the kind of rock making up the matrix inside, we can tell that it almost certainly came from the Columbus Limestone (Middle Devonian, Eifelian).

In the top image it is apparent that this fossil has bilateral symmetry, a heart-shaped cross-section, and a ribbed calcitic shell. This is the dorsal view.
2 Hippocardia 2Flipping the specimen upside-down, we now have a view of the ventral portion. Again we see the ribs and bilateral symmetry.
3 Hippocardia side viewThis side view shows that the ribs extend from the dorsal to the ventral sides and are angled to the axis of the shell. That’s about all we can tell. (And this is the best specimen of a rostroconch we have! Thank you again, Cameron.)
4 CzechVirtualRostroThis diagram of a complete rostroconch (from the Czech Virtual Museum). This is a side view of a species that does not have the dorsal-ventral ribbing. The shell is superficially like that of a bivalve (clam), but the valves are fused together and their is a distinctive tube (rostrum) extending to the posterior. Much study and debate about the rostroconchs has at least confirmed that these are a class of mollusks separate from the bivalves. They lived semi-infaunally with the rostrum extending into the seawater to channel a flow of water into the body chamber for filter-feeding, much like infaunal bivalves today that have siphons. Rostroconchs and cephalopods appear to be sister groups, and some rostroconchs may have evolved into the scaphopods. Plenty of arguments to go around, though, on the evolution and diversification of mollusks
5 Thomas 1843 p 976 Thomas pl 8 fig 10 1843Captain Thomas Brown (1785-1862) named the genus Hippocardia in 1843. He was a Scottish naturalist who studied many topics, including mollusks. Above are the sections of his book The Elements of Fossil Conchology that describe and illustrate Hippocardia (considering it a bivalve). Captain Brown was born in Perth and went to school in Edinburgh. He joined the militia at 20, becoming a captain at 26. When he was transferred to Manchester, England, Brown acquired an interest in nature. He bought a flax mill after leaving the military, but it burned down while still uninsured. He thus turned to nature writing for support. He was became a Fellow of the Royal Society of Edinburgh in 1818, and in 1840 he was appointed curator of the Manchester Museum. He retained this position for the rest of his life. He was later a Fellow of the Linnean Society and a member, in classic 19th Century fashion, of several other groups, including the Wernerian, Kirwanian and Phrenological Societies. (I love the addition of phrenology to his interests!) The marine gastropod Zebina browniana d’Orbigny, 1842, was named after him. An interesting character, this Captain Brown, but I’ve been unable to find a single portrait of him.


Brown, T. 1843. The elements of fossil conchology according to the arrangement of Lamarck; with the newly established genera of other authors. Houlston & Stoneman, London; 133 pages.

Hoare, R.D. 1989. Taxonomy and paleoecology of Devonian rostroconch mollusks from Ohio. Journal of Paleontology 63: 838-846.

Pojeta, J., Jr., Runnegar, B. 1976. The paleontology of rostroconch mollusks and the early history of the phylum Mollusca. United States Geological Survey Professional Paper 968: 1-88.

Pojeta, J., Jr., Runnegar, B., Morris, N.J. and Newell, N.D. 1972. Rostroconchia: a new class of bivalved mollusks. Science 177: 264-267.

Runnegar, B., Goodhart, C.B. and Yochelson, E.L. 1978. Origin and evolution of the Class Rostroconchia [and discussion]. Philosophical Transactions of the Royal Society B: Biological Sciences 284(1001): 319-333.

Wagner, P.J. 1997. Patterns of morphologic diversification among the Rostroconchia. Paleobiology 23: 115-150.

Wooster’s Fossil of the Week: A tall brachiopod from the Devonian of western Russia

November 20th, 2015

1 Ladogia Nalivkin, 1941In the summer of 2009 I had a field adventure in Russia. It was an extraordinary time. I learned considerable amounts of Russian geology and paleontology, of course, and was immersed in the Russian geological culture. Along the way I collected the above unusual brachiopod. We are looking at its posterior (where the articulating hinge is), with the ventral valve below and dorsal valve above.
2 Ladogia Nalivkin, 1941This is the anterior view of the same specimen showing the junction between the valves (the commissure). The brachiopod is Ladogia Nalivkin, 1941, a rhynchonellid from the Upper Devonian (Frasnian) of the Central Devonian Field somewhere along the Syas River in the Leningrad Oblast of western Russia. We can immediately see that this brachiopod is very tall for its kind, with a strongly defined fold (the top part of the “anticline” in the dorsal valve) and sulcus (the lower folded surface in the  ventral valve). Note that the sulcus has several encrusting organisms, including eroded microconchids.
3 Ladogia Nalivkin, 1941The side view shows the dramatic upward sweep of the dorsal valve and the fine radiating ornamentation. The tall fold was effective in separating the incoming water for filter-feeding from the outflow of filtered water, essentially functioning like a chimney. Many brachiopods have such a fold and sulcus, but few have a set of such amplitude.
4 Nalivkin, Dmitrii VasilevichLadogia was described by Dmitrii Vasil’evich Nalivkin (1889-1982) in 1941. Nalivkin was a Soviet paleontologist and geologist born in 1889 in St. Petersburg. He graduated from the Institute of Mines in Petrograd (the name was changed from St. Petersburg) in 1915. In 1917 he joined the Geological Commission of Russia, staying a member through its many changes for over six decades. In 1920 he became a professor at the Institute of Mines after, we presume, the political situations from the Great War, the Bolshevik Revolution and the Russian Civil War calmed down. He is notable for giving the first lecture series on facies theory in the USSR in 1921. After World War II he was chairman of the Turkmen section of the Academy of Sciences. In 1954 he was made chairman of the Interdepartmental Stratigraphic Committee of the Academy of Sciences of the USSR. In 1954 he was appointed chairman of the Interdepartmental Stratigraphic Committee of the Academy of Sciences of the USSR. Nalivkin specialized in stratigraphy and paleontology of the Paleozoic, especially the Devonian and Carboniferous. He is best known for his geological maps of the USSR, for which he received the Lenin Prize in 1957. Here’s a man who saw a lot of history in his time.


Nalivkin, D.V. 1941. Brachiopods of the Main Devonian field. Akademii Nauk SSSR Trudy 1: 139-226.

Sokiran, E.V. 2002. Frasnian-Famennian extinction and recovery of rhynchonellid brachiopods from the East European Platform. Acta Palaeontologica Polonica 47: 339-354.

Zhuravlev, A.V., Sokiran, E.V., Evdokimova, I.O., Dorofeeva, L.A., Rusetskaya, G.A. and Malkowski, K. 2006. Faunal and facies changes at the Early-Middle Frasnian boundary in the north-western East European Platform. Acta Palaeontologica Polonica 51: 747-758.

Wooster’s Fossil of the Week: an upside-down nautiloid from the Devonian of Wisconsin

October 16th, 2015

1 Poterioceras calvini Milwaukee Formation DevonianThis lump of a fossil in Wooster’s teaching collection requires some explanation. It is not particularly well preserved, but it is our only representative of an interesting group of nautiloid cephalopods. The label that came with it says it is Poterioceras calvini, but I see no reason to believe it. There are simply not enough characters visible to identify it to the genus level, let alone the species. We should confine it to a higher taxon: Order Oncocerida Flower in Flower and Kummel, 1950. It comes from the Wisconsin Dolomite (Devonian) exposed in the city of Milwaukee.
2 Poterioceras calvini Milwaukee Formation DevonianOn the left-hand side (with the scale) of each image you may barely make out vertical partitions, shown as faint lines. These are sutures, which represent the junction between internal septal walls and the outer shell. The shell has dissolved (since it was made of more soluble aragonite), leaving this internal mold fossil. The right side of the fossil shows no such partitions because it is where the large body chamber was located. The nautiloid animal lived in the body chamber, with the septal walls (and the chambers they delineated) behind it as the phragmocone.
3 Gomphoceras cartoon 585This diagram from Wikipedia may make sense of this anatomy. The chambered phragmocone is shown in the top left, colored yellow; the body hangs below it in the body chamber. The phragmocone was filled with a mixture of gases and liquids, giving it positive buoyancy relative to the negatively-buoyant body chamber. The nautiloid thus in life hung upside-down facing the seafloor as it floated about. The cartoons on the right show the shell itself, including the keyhole aperture that kept the body from falling out.
4 orthoconeCompare this to the typical orientation of a Paleozoic nautiloid (above). Both of these nautiloid types were nektic (swimming) predators. The oncocerid just did it by hanging upside-down!
5 RH Flower 585The Order Oncocerida was named and described by one of the 20th Century’s most eccentric paleontologists, Rousseau Hayner Flower (1913-1988). I never met Dr. Flower, but I stumbled into a memorial session for him at the 1988 annual Geological Society of America meeting, which was held that year in Denver. Some people were barely holding back tears, others were laughing, and one crusty old paleontologist stormed out muttering “He was a bastard!”. I knew then that Flower was a character. (The photograph is from Wolberg, 1988, inside front cover.)

Rousseau Flower was born in a small town in upstate New York in 1913. He was both musically and scientifically gifted, winning a scholarship to Cornell University where he trained in entomology, eventually earning an M.A. degree there. An interest in fossil dragonflies drew him into paleontology, and a chance to take an extended geological field trip sealed his new interest in fossils. He had an eventful few years in the New York State Museum and the University of Indiana, finally earning his PhD at the University of Cincinnati in 1939. After bouts of unemployment during the war years, he went back to the New York State Museum to fill various temporary positions. In 1951 he took a job as Stratigraphic Geologist at the State Bureau of Mines & Mineral Resources in New Mexico, where he stayed for the rest of his life.

Flower took on his new Western identity with gusto, wearing cowboy garb and sometimes brandishing a bullwhip. He traveled the world studying corals and cephalopods and amassing an enormous collection that people are still sorting through. He published some 1800 pages of paleontological work, naming dozens of new taxa and making major contributions to our understanding of cephalopod evolution and paleobiology, coral systematics, and western North American stratigraphy. He was acerbic and, shall we say, confident in his analyses, so he made as many enemies as friends. Over half of his work was published in the memoir series of the New Mexico Bureau — so much that some suspected it was his private journal. On top of all this, he was also a prominent music and arts critic in New Mexico. Rousseau Flower earned his fearsome reputation!


Flower, R.H. and Kummel, B. 1950. A classification of the Nautiloidea. Journal of Paleontology 24: 604-616.

Mutvei, H. 2013. Characterization of nautiloid orders Ellesmerocerida, Oncocerida, Tarphycerida, Discosorida and Ascocerida: new superorder Multiceratoidea. GFF 135: 171-183.

Wolberg, D.L. 1988. Rousseau Hayner Flower, p. viii-x, in: Contributions to Paleozoic Paleontology and Stratigraphy in Honor of Rousseau H. Flower. New Mexico Bureau of Geology & Mineral Resources, Memoir 44, 415 pp.

Wooster’s Fossils of the Week: A rugose coral and its encrusters from the Middle Devonian of New York

October 9th, 2015

Heliophyllum halli Bethany Center Centerfield 2 585This week’s fossils were found on a most excellent field trip to the Niagara region of New York in August. One of our outcrops was a small patch of gravel in Bethany Center where the Centerfield Limestone Member of the Ludlowville Formation (Givetian, Middle Devonian) was exposed. My colleagues and I found many interesting fossils here. The largest specimen I collected was the above rugose coral.
1 Heliophyllum halli Bethany Center Centerfield 2 copyIt is Heliophyllum halli Milne-Edwards and Haime, 1850. This species is very common throughout the Devonian Hamilton Group of New York, Ontario and surrounding areas. The 90-degree bend in the specimen is a result of the living coral being knocked over onto its side and then twisting to grow upwards again.
3 Rugose Bethany Center Centerfield 3These corals are called “rugose” because of their “wrinkled” exteriors, easily seen in this view. The solitary forms, like this one, are a single corallite that held one polyp in life. Their conical growth form gives them another nickname: “horn corals”. Rugose corals also come in colonial varieties, which we’ve covered before in this blog. Their skeletons are made of thick calcite, so they are almost always well preserved. These corals are distinguished from others by their strong internal vertical walls (septa) and relatively few horizontal or angled partitions (tabulae and dissepiments). They lived like most other corals as sessile benthic (stationary on the bottom) predators catching food with their tentacles. It is still uncertain whether they had photosynthetic symbionts (zooxanthellae) like modern corals. Emily Damstra has a nice reconstruction of living Heliophyllum halli.
4 Encrusting Bryozoan Bethany CenterThis particular coral has a collection of encrusting organisms on its exterior. Above is a remnant of a bryozoan.
5 Microconchid Bethany CenterThe encrusting coiled shell in the lower left is a nice microconchid (a mysterious lophophorate) and at the top is another type of bryozoan. Many of these encrusters are found on eroded parts of the coral skeleton, so they likely encrusted it after death.

Heliophyllum halli was named by Milne-Edwards and Haime in 1850. We’ve introduced Henri Milne-Edwards (1800-1885) before, and even James Hall (1811–1898) for whom the species is named. Jules Haime (1824-1856) is less known. He died too young at age 32, which may explain why we have no images of him. HIs father was a prominent physician, Auguste Haime (1790-1877). Jules, like many 19th Century paleontologists, started in medicine (studying in Tours) but gravitated toward the excitement in natural history, becoming a zoologist and paleontologist. He specialized in corals, joining up early in his career with Milne-Edwards. Haime rose fast in his new profession. One year before his death he became a professor of natural history at the Lycée Napoléon in Paris. In 1856 he was appointed vice-president of the Société géologique de France, but died a few months later.


Baird, G.C. and Brett, C.E. 1983. Regional variation and paleontology of two coral beds in the Middle Devonian Hamilton Group of Western New York. Journal of Paleontology 57: 417-446.

Brett, C.E. and Baird, G.C. 1994. Depositional sequences, cycles, and foreland basin dynamics in the late Middle Devonian (Givetian) of the Genesee Valley and western Finger Lakes region. In: Brett, C.E., and Scatterday, J., eds., Field trip guidebook: New York State Geological Association Guidebook, no. 66, 66th Annual Meeting, Rochester, NY, p. 505-585.

Milne-Edwards, H. and Haime, J. 1850-1854. A monograph of the British fossil corals. London, Palaeontographical Society. 736 pages.

Wooster’s Fossil of the Week: A mystery fossil for my Invertebrate Paleontology students

September 4th, 2015

1 Stereolasma singleAt the beginning of my Invertebrate Paleontology course I give each student a fossil to identify by whatever means necessary. I challenge them to take it down to the species level, and tell me its age and likely place of collection. The fossil this year is shown above: the rugose coral Stereolasma rectum (Hall, 1843) from the Middle Devonian of New York. I collected the specimens on my western New York adventure last month from the Wanakah Shale Member of the Ludlowville Formation at Buffalo Creek in Erie County. (There were a lot of them! This coral is so common that you can buy them online at science supply stores.)

The corals I collected were well weathered on the Devonian seafloor. You can see some evidence of this in the exterior which shows opened tunnels of borings. They were not appreciably weathered on the outcrop because they were directly excavated from the shale matrix.
2 Stereolasma cross section 585This is a cross-section through one of the S. rectum specimens. The internal radiating calcitic partitions (septa) are well preserved by clear calcite cement. There appear to be at least two generations of sediment that penetrated into the interior after the death of the polyp. The posthumous events affecting these corals may be more interesting than their life histories.

That awkward species name comes from the Latin rectus for “straight”. The anatomical rectum that we all know well comes from the same root but is based on a misconception by early anatomists that the terminal part of the large intestine in mammals is straight. It’s not, as a Google search will quickly show you. (I decided against including an image.)
3 Wanakah coralsReferences:

Baird, G.C. and Brett, C.E. 1983. Regional variation and paleontology of two coral beds in the Middle Devonian Hamilton Group of Western New York. Journal of Paleontology 57: 417-446.

Brett, C.E. and Baird, G.C. 1994. Depositional sequences, cycles, and foreland basin dynamics in the late Middle Devonian (Givetian) of the Genesee Valley and western Finger Lakes region. In: Brett, C.E., and Scatterday, J., eds., Field trip guidebook: New York State Geological Association Guidebook, no. 66, 66th Annual Meeting, Rochester, NY, p. 505-585.

Busch, D.A. 1941. An ontogenetic study of some rugose corals from the Hamilton of western New York. Journal of Paleontology 15: 392-411.

Stumm, E.C. and Watkins, J.L. 1961. The metriophylloid coral genera Stereolasma, Amplexiphyllum, and Stewartophyllum from the Devonian Hamilton group of New York. Journal of Paleontology 35: 445-447.

A day’s excursion into the Middle Devonian of western New York

August 7th, 2015

1 Wanakah at Buffalo CreekLOCKPORT, NEW YORK (August 7, 2015) — Today Andrej Ernst and I were able to join Brian Bade and his friends on a collecting trip up Buffalo Creek in Erie County, New York. Our goal was simply to look for interesting fossils in the Wanakah Shale Member of the Ludlowville Formation (Middle Devonian) and enjoy the fellowship of fossil enthusiasts. Success on both counts. It was a great day, and rather fun wading through the cool waters of the creek as we examined the shale on the banks.

2 Wanakah TrilobiteHere is an external mold of a trilobite in the soft Wanakah Shale. An external mold is an impression of the exterior of the organism. If you look at this upside-down it pops into reverse relief! This fossil is not recoverable because it would break into bits with any attempt to hammer it out. Andrej and I found plenty of bryozoans here, along with other cool fossils.

3 Bethany Center Centerfield LimestoneAs a bonus we also were able to visit the Bethany Center exposure of the Centerfield Limestone, also Middle Devonian. There isn’t much left of the exposure, as you can see, but we still found numerous encrusting organisms (sclerobionts) on brachiopods and the abundant rugose corals. We also got plenty of sun here.

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