Following in the Footsteps of Isaac Lea’s Historic Footprints

Scientists today undertake research in a single scientific field, usually within a narrow sub-discipline. For instance, modern scientists who call themselves geologists are actually specialists in subfields of geology, such as volcanology, the study of volcanoes and volcanic activity, and paleontology, the study of fossils and forms of life existing in prehistoric or geologic times. However, in the nineteenth century, most who conducted scientific research — amateur and professional alike — regularly worked in more than one field. One such Renaissance man, Isaac Lea (1792–1886), was an amateur scientist best remembered by students of natural history for his research of freshwater clams, or malacology, but who also made important scientific contributions to paleontology and mineralogy. On April 5, 1849, Lea made his greatest paleontological discovery — fossil footprints, at Mount Carbon in Schuylkill County. His discovery — and the bitter scientific controversy it ignited — are part of a largely forgotten chapter in the history of science.

Born in Wilmington, Delaware, on March 4, 1792, Isaac Lea lived most of his life in Philadelphia. He descended from John and Hannah Hopton Lea, Quakers who had immigrated to Delaware from Gloucestershire, England, with William Penn on his second visit to his colony, arriving at Chester on November 30, 1699. His father, James J. Lea (1759–1825), was a wholesale merchant. Lea’s mother, Elizabeth Gibson Lea (1762–1833) shared her interest in botany with her son. Isaac Lea’s life-long friendship with Lardner Vanuxem (1792–1848), who became an accomplished professional geologist, fostered his interest in geology and mineralogy. Although Lea’s schooling intended him for a career as a physician, at the age of fifteen he began working in his brother John’s wholesale import business in Philadelphia. During the War of 1812, Lea and Vanuxem joined a military company organized for local defense. Although the unit never saw action, the Religious Society of Friends expelled him for his non-pacifist activities.

In 1815, he joined the Academy of Natural Sciences in Philadelphia, which had been founded just three years earlier, in 1812, “for the encouragement and cultivation of the sciences and the advancement of useful learning.” Lea’s first published article, on the minerals found in the Philadelphia vicinity, appeared in the Proceedings of the Academy in 1817, and launched an extensive career in scientific publishing that culminated in 279 books, articles, and essays. Geology remained a lifelong interest and pursuit for Lea. His lengthiest published work on geology appeared in 1833; the 227-page book, Contributions to Geology, is a descriptive catalogue of fossils, primarily of Cenozoic age, from the vicinity of Claiborne, Alabama. His scientific bibliography lists twenty-seven articles on geology published between 1818 and 1868, on a wide variety of topics, among them minerals, coal, fossils, and earthquakes.

Lea married Frances Anne Carey (1799–1873) on March 8, 1821, a marriage that lasted fifty-two years, until her death at the age of seventy-four. His father-in-law, Matthew Carey (1760–1839), owned Matthew Carey & Sons, one of the most successful publishing houses in Philadelphia. After his marriage, Lea joined the firm and worked for thirty years, until retiring in 1851 from the company, which had been renamed Blanchard & Lea. Isaac and Frances Lea were the parents of four children, Matthew Carey, who died not long after his birth in 1822; Matthew Carey (1823–1897), the foremost American photographic chemist of his day; Henry Charles (1825–1909), an accomplished and highly respected historian of Medieval Europe, most noted for a series of books he wrote on the Inquisition; and Frances (1834– 1894), wife of Leander T. Chamberlain, who bequeathed a collection of gemstones acquired by her father to the United States National Museum, now part of the collections of the Smithsonian Institution’s National Museum of Natural History.

Isaac Lea’s principal scientific interest, the study of living freshwater clams, began in 1825, and his first publication on this subject — on the widespread genus Unio — appeared two years later. Lea began by studying the collections assembled by Major Stephen Harriman Long (1784–1864), an engineer, explorer, and military officer, along the Ohio River and sent to the academy, as well as shells a brother had collected near Cincinnati. Over the course of a half-century of research, Lea named a staggering 1,842 species of fifty genera of freshwater and terrestrial mollusks. He wrote papers on the physiology of clams based on experi- ments, such as their sensitivity to light. He achieved recognition primarily as a malacologist, a student of living clams.

Despite his years of research, writing, and publishing, assessment of Lea’s scientific legacy as a malacologist is mixed. On the one hand, Lea pioneered the study of freshwater clams and was the first scientist to provide detailed descriptions and beautiful illustrations of many newly discovered species. On the other hand, he had no appreciation of the variety of shell forms within a single freshwater clam species, so many of the species he named are not distinct. The best current scientific estimate is that only less than one third of the names he coined for freshwater mollusks are valid.

After retiring from the publishing company at the age of fifty-nine, Lea devoted much of his time to scientific research. He served as the president of the Academy of Natural Sciences for several years and as president of the American Association for the Advancement of Science in 1860. Harvard College awarded him an honorary degree in 1852. In his later years, he returned to mineralogy and was among the first researchers in North America to examine minerals under a microscope.

Lea’s income from the family publishing business made him wealthy, enabling him to not only pursue science, but also to indulge in other hobbies, such as collecting art. He returned from a trip to Italy with his son Henry Charles Lea in 1852 with what peers considered to be among the finest collections of Italian works of art in the United States. His trips to Europe in 1832 and 1852 were family junkets that mixed science with social affairs, during which Lea circulated among the wealthy and elite in Great Britain and on the continent. His affluence allowed him to purchase 250 offprints of every article that he published, which he periodically bound and sent to colleagues and institutions in both North America and Europe. During his lifetime, Lea amassed an enormous private collection — tens of thousands of specimens — of mollusks, minerals, and fossils, which he bequeathed, along with his library, to the Smithsonian Institution, Washington, D.C.

The fossil footprints Lea discovered at Mount Carbon date to the Mississippian age, 330 million years ago. He visited the Pottsville area for family and business interests, not primarily for scientific studies. In 1835, his brother-in-law Henry Charles Carey had quit the publishing firm and invested more than $120,000 — $2,336,883 today — of his own and partners’ money in 3,200 acres of coal lands near St. Clair, three miles north of Pottsville, the county seat, becoming one of the largest landowners in the area. Lea’s sister-in-law Eliza Catherine Carey Baird (1795–1881) lived in Pottsville. She was the widow of Thomas James Baird (1794–1842), an 1814 graduate of the United States Military Academy at West Point and an incorporator, in 1839, of the Fishing Creek Railroad Company to serve Schuylkill County. Both Lea and Baird were helpful to the family’s investments in coal mining operations with their scientific, geological, and technical knowledge. In History of Northampton, Lehigh, Monroe, Carbon and Schuylkill Counties, published in 1845, author Israel Daniel Rupp (1803–1878) mentioned a “farm now owned by Cary, Lee and Hart, of Philadelphia,” near Mount Carbon. In addition to his association with the Carey family’s publishing company, prominent Jewish philanthropist Abraham Hart (1810–1885) was also engaged in diverse manufacturing and mining firms.

By day, Isaac Lea was a publisher and speculator; in the early 1830s he became the principal partner in the Dauphin and Susquehanna Coal Company, which owned forty-two thousand acres on the east bank of the Susquehanna River. By night, he devoted himself to geology, chemistry, and paleontology. While in the coal region he examined the enormous exposures of rocks rising above the banks of the Schuylkill River and its tributaries. An easily reached outcrop comprised the red rocks along the turnpike road near the hostelry known variously as the Mansion House or the Mount Carbon Hotel. In 1849, he published his initial report of the discovery. “I have discovered the foot prints, in bas relief, of a reptilian quadruped . . . on the 5th of April last, in the examination of the strata in the gorge of the Sharp Mountain, near Pottsville, Pa., where the Schuylkill breaks through it, a large mass of remarkably fine old red sandstone attracted my attention.”

Lea knew that in 1845, a medical doctor, Alfred T. King, had published a report of fossil footprints found in the “coal measures,” or coal-bearing rocks, of Westmoreland County in western Pennsylvania. The tracks Lea discovered were in rocks older than the “coal measures,” and he contended they represented remains of a reptile “lower in the series than has yet been observed” and were “the record of the oldest saurian yet observed.” The slab Lea found contained six footfalls, which he gave a new scientific name, Sauropus primaevus (“primeval lizard track”). He apparently overlooked the fact that the term Sauropus had been previously coined for another type of track. Lea introduced a “synonym” that a Smithsonian Institution paleontologist replaced years later with Palaeosauropus.

Lea fervently believed he had made a truly epochal discovery, pushing back the fossil record of reptiles into the Devonian time interval, between 360 and 408 million years ago. Not only did he give a first report, in 1849, of his discovery in Proceedings of the American Philosophical Society, but he also dispatched brief notices published in 1850 in Yale College’s American Journal of Science, Zeitschrift der Deutsche Geologische Gesellschaft (Magazine of the German Geological Society), and Report of the British Association for the Advancement of Science.

In 1853, he published an extensive report on the Mount Carbon tracks in Transactions of the American Philosophical Society. His article also offered a critical piece of detailed information about where he found the tracks. In describing the fossil site, he wrote, “its position was on the west side of the turnpike road, about a mile east of the town of Pottsville, and a few hundred feet east of Mount Carbon Hotel.”

Mount Carbon is a tiny borough — the 2000 census counted 87 residents — and its most recent claim to fame is that voters elected one of the youngest mayors in the nation’s history, Jeffrey J. Dunkel, inaugurated one month shy of his nineteenth birthday, in January 2002. Located one mile south of Pottsville, Mount Carbon in 1850 consisted of only a few buildings. The hotel in Mount Carbon was originally a single building purchased about 1829 by John White, president of the Philadelphia and Reading Railroad Company. Renovated and significantly enlarged, with the addition of a second structure, the property became known as the Mansion House.

In his history, Rupp reprinted a passage describing Mount Carbon that had originally appeared in the Pottsville Advocate, the city’s second English language newspaper, early in 1831.

Its situation is romantic, the abrupt hills, rising almost perpendicularly around, are strikingly grand, while the Schuylkill [River], winding through gorges of the mountain, completes a scene of picturesque beauty unsurpassed by the points in whose praise our northern tourists are so fluent. Sharp mountain itself is a remarkable curiosity, resembling a rampant-boundary to the coal region on the south.

Eli Bowen in his 1852 Pictorial Sketch-Book of Pennsylvania, published by Willis P. Hazard, of Philadelphia, noted, “near the railroad, is the Man- sion House, now conducted by Mr. Head, one of the most distinguished caterers on the American continent.” Bowen extolled the locale’s natural beauty for travelers and sojourners.

This hotel has been materially enlarged and improved. It is the only establishment, in this part of the country, specially adapted for the accommodation of summer visitors to the coal region — being large and airy, and sufficiently near Pottsville to render it readily accessible, and sufficiently distant to avoid its dust and business excitements. It has an extensive and beautiful park attached, with bowling house, and other arrangements for out-door amusements. The location, as may be supposed from a glance at it, is extremely cool and pleasant in the summer, as well as quiet and retired. The nights are particularly refreshing, and sleep is to be enjoyed, after the heat of the day, with a vigor perfectly unknown in the crowded city. Some time since, the family of Interbide [sic], formerly Emperor of Mexico, and the family of Mr. [John] Tucker, the distinguished President of this [Philadelphia and Reading Railroad Company] road — (and Emperor of the American Railway Managers) made this hotel their annual summer quarters.

Seven years earlier Israel Rupp had described the Mansion House as “a beautiful edifice of stone, forty-five feet wide by eighty-two, exclusive of the piazza, which presents a promenade to each story, embracing a view of the mountain scenery around.” The hotel was torn down about 1930.

In the early nineteenth century, residents and travelers alike called the road in front of the hotel the Centre Turnpike; by the end of the century it had become known as Centre Street. The hotel occupied what is now the southwest corner of the intersection of Centre Street and Main Street. Centre Street runs from north to south, and the hotel was located on the west side of the street. Researchers best describe Lea’s tracksite as being on the west side of Centre Street, one mile south of Pottsville, and several hundred feet south of the hotel.

A painting owned by the Historical Society of Schuylkill County, headquartered in Pottsville’s former Female Grammar School, depicts Mount Carbon about 1855. According to Isaac Lea’s description, he found a large rock slab bearing the footmarks “in-situ” as part of a large outcrop of rock. This rocky outcrop is depicted in the painting as a reddish brown earthen outcrop to the left (or south) of the hotel. Dr. Peter Yasenchak, a long time resident of Pottsville and director of the historical society, says part of a wall of the Mansion House is still visible. A pizza shop occupies the site of the old hotel but a section of an old retaining wall stands on the building’s south side. Farther south, on the west side of Centre Street, is a several-hundred-foot long outcrop of reddish-brown rock. This outcrop is Isaac Lea’s original tracksite for Palaeosauropus primaevus. The talus, a sloping mass of rock debris at a cliff base, contained the fossil footprints.

Of the two slabs of rocks with footprints Lea collected at the site, a plaster cast of the larger piece, with six footfalls preserved, is in the collections of the Smithsonian Institution, Washington, D. C. The smaller section, containing a single hand-foot set, in the collections of the Academy of Natural Sciences, is considered the type specimen of Palaeosauropus primaevus. Lea believed the tracks to be those of a reptile, but scientists now know they had been made by an amphibian.

Lea’s initial published report of the Mount Carbon footprints sparked controversy, driven by the judgment of Henry Darwin Rogers (1808–1866), State Geologist of Pennsylvania, who believed the tracks were not as old as Lea claimed. Lea opened his 1853 article with a counterattack on Rogers that consumed nine of its eleven pages. Two years later, Lea privately reprinted the article in which he enlarged the illustrations, but did not alter the text.

In 1850, Rogers attended the American Association for the Advancement of Science (AAAS) meeting in New Haven, Connecticut, where he pronounced Lea’s tracks to be “of an age essentially later than that attributed to them,” adding, “instead, therefore, of constituting a record of antique reptilian life, earlier than any hitherto discovered, by at least a whole chapter in the geological book, they carry back its age only by a single leaf.”

Rogers’s sarcastic remarks constituted a pointed rebuke of the main significance Lea claimed for his discovery. During the same meeting, Louis Agassiz (1807–1873), a renowned paleontologist and expert on fossil fishes, suggested the tracks were not even those of a reptile but, instead, were marks of “the pectoral and ventral fins of fishes of an ancient type, which probably had some power of locomotion out of water.”

Rogers participated in the following year’s AAAS meeting in Albany, New York, and upstaged Lea’s discovery by showing his own collection of reptile tracks found near Lea’s site and, significantly, from older strata. Agassiz remained consistent and objected to identifying Rogers’ fossils as reptilian tracks.

The core of the disagreement lay in what geological age Isaac Lea and Henry Darwin Rogers assigned to the red rocks exposed at Mount Carbon. They variously referred to these rocks as “red shales,” “red shale formation” or, more technically, as “Formation XI” in the formal terminology of the Geological Survey of Pennsylvania. Scientists now refer to these rocks as the Mauch Chunk Formation; they received the name in 1876 from the Carbon County seat of Mauch Chunk (now Jim Thorpe).

By the 1840s, a succession of rocks had been identified and established in England against which most American geologists compared the rocks of the mountainous regions of the eastern United States, including Pennsylvania. The relevant British succession begins with red rocks termed Old Red Sandstone, or Devonian in age by modern understanding, overlain by the Mountain Limestone, of the Mississippian age, and then the Coal Measures, dating to the Pennsylvanian period, which ended about 286 million years ago. Lea cited the published opinions of noted American geologists, including the State Paleontologist of New York, James Hall (1811–1898), and the famous British geologist, Charles Lyell (1797–1875), one of the conceptual founders of the science of geology. Both Hall and Lyell believed the red rocks beneath the coal beds of New York and adjacent areas correlated to Great Britain’s Old Red Sandstone.

Lea advocated this specific correlation, an opinion that many of his contemporaries respected and supported. Such a correlation made the Mount Carbon footprints the oldest evidence of “reptiles.” At the time, only the coal measures in Europe and North America produced fossil bones or footprints thought to be reptilian. He described the Mount Carbon tracks as evidence of the “oldest ‘air-breathing animal’ then known in the sedimentary rocks of the globe.”

Rogers, however, knew something about the red rocks at Mount Carbon that Lea and others did not. He summarized his knowledge in the monumental two-volume Geology of Pennsylvania, published in 1858 by J. B. Lippincott of Philadelphia. Rogers knew that about 150 miles southwest of Schuylkill County, the “red shale formation” is also exposed from Cambria through Somerset Counties and into Maryland, where it includes an interval of marine limestone of Carboniferous (or Mississippian) age. Rogers declared the red rocks to date to the Carboniferous Age, a contention accepted by paleontologists today. Although Lea proved incorrect in considering his tracks equivalent in age to the Old Red Sandstone, paleontologists today believe — given the fact that he based the geological age on the best data available — it’s fair to conclude Isaac Lea was wrong for the right reasons.

Rogers was not only correct about the geological age of the Mount Carbon footprints, but he attempted to claim the last word in print in his Geology of Pennsylvania. He also saw the Mount Carbon footprints as central to an important disagreement he had with Charles Lyell and other British geologists of the time who have since been called uniformitarians. These geologists did not believe in a progression of life forms through geological time and, in particular, they did not believe that so-called “lower” vertebrate animals, such as reptiles, had appeared before “higher” vertebrates, such as mammals.

In an article published in 1855 by the Boston Society of Natural History, Rogers had noted that the Mount Carbon footprints were relevant to “certain cardinal doctrines of geology, especially on the theory of a progressive development in the extinct inhabitants of the earth.” He further argued that across geological time, the fossil tracks of reptiles, such as those found at Mount Carbon, appeared earliest, followed by the tracks of birds and then of mammals, indicating a successive, or “progressive,” origination of these groups of animals.

This law of a progressive rise in the character of the footprints, like that so generally recognized in regard to the organic remains themselves, distinctly refutes the view urged by Sir Charles Lyell, and some other disciples of the Huttonian theory of the earth’s history. Fancying a uniformity in the series of past changes in the animate and inanimate world, they contend that the evidence in support of the theory of the progressive development of organic life is inconclusive.

Henry Darwin Rogers had stolen Isaac Lea’s thunder! Not only had he discounted the significance Lea had attributed to his footprints, but Rogers also propelled the tracks into one of the most highly charged scientific debates of the day.

For Lea and Rogers, the scientific discussion of the Mount Carbon footprints apparently ended in the 1850s. As for Rogers’ critique of Lyell, it remained for Lyell’s friend, Charles Darwin (1809–1882), to change the great geologist’s mind about progressive development by publishing his epochal On the Origin of Species in 1859. Rogers’ arguments for progressive development based on Lea’s footprint discoveries had not convinced Lyell or other like-minded geologists opposed to progression, and the discovery of the “world’s oldest footprints” at Mount Carbon slipped into scientific obscurity.

Lea never conceded to Rogers on the age of the Mount Carbon footprints, and he made sure he had the last word. Thirty years later, in 1885, nearly two decades after Rogers’s death, Newton Pratt Scudder published a “biography” of Lea. Little more than hagiography, scholars believe it had been ghostwritten by Lea, given the diary-like details of his travels and its laudatory language throughout. The Published Writings of Isaac Lea, L.L.D. includes three pages of extracts from various letters written in 1855 by famous geologists to the subject, extolling his discovery of the footprints at Mount Carbon. It comes as little surprise to today’s paleontologists that Isaac Lea’s last words on the Mount Carbon footprints were the same as his first, namely the footprints remained “the oldest case of an air-breathing animal on record.”

Understanding Undertracks

One of the fossil footprint slabs collected by Isaac Lea at Mount Carbon in 1849 — a piece of red sandstone a bit larger than an ordinary dinner plate —remains for scientific study in the collections of the Academy of Natural Sciences in Philadelphia. The slab preserves two tracks, one of the hind foot (pes) immediately behind one of the forefoot (manus). However, the tracks are incomplete; they preserve only clear imprints of three fingers (digits) in the manus and four in the pes and lack complete sole (heel) imprints. This incompleteness indicates that the tracks on the slab are what paleontologists call undertracks.

A track forms when an animal impresses its foot into loose particles, usu- ally called sediment, on the ground. The track is the structure formed on the ground surface and, because it is exposed to air, it must be buried quickly to be preserved. However, the weight of the animal also deforms the sedi- ment below the ground surface, producing what paleontologists refer to as undertracks. These undertracks resemble the track above them, but the amount of resemblance depends on several factors that control the degree to which the track deforms underlying sediment. The degree of deforma- tion is produced by the greater weight of the animal, and the consistency of the sediment, especially its viscosity. In general, the undertracks closest to the tracks most resemble the track, and those farther away, or deeper, resemble it less. An individual track can be underlain by dozens of under- tracks, depending on the layering of the sediment. Most important is that undertracks are instantly buried the moment they are formed, and have a greater chance of being preserved as fossils than do tracks. This is why paleontologists believe that most footprint fossils are actually undertracks, not the tracks formed at the ground surface.

The undertracks of Palaeosauropus primaevus collected by Lea are reflections of tracks in which the manus has four digits and the pes has five. Both manus and pes in the track have sole imprints. Scientists have con-firmed this, based on more complete footprints of Palaeosauropus primaevus that have since been collected near Mount Carbon. The lack of these features suggests the undertrack of Palaeosauropus primaevus formed several layers below the track, at a depth in which all the details of footprint structure were not preserved.

Travel Tips

Since the days of nineteenth-century natural scientist Isaac Lea (1792–1886), naturalists, paleontologists, archaeologists, and anthropologists have continually made new discoveries and subsequently revised prevailing theories, many of them time-honored and difficult to abandon. Pennsylvania’s museums are constantly adding new wonders to teach visitors about past millennia, including a newly remodeled dinosaur center opening this autumn at the Carnegie Museum of Natural History in Pittsburgh. Until its unveiling, individuals can inspect progress on the new center, “Dinosaurs in the World,” being captured by time-lapse cameras.

Opened in 1929, the Reading Public Museum in the Berks County seat has collected specimens that now number in the hundreds of thousands, including insects, birds, mammals, and minerals, as well as objects of anthropological and historical value from all over the world. In addition, the museum holds thousands of priceless works of art, Native American artifacts, and antiquities. The museum’s dinosaur and natural science galleries highlight mounted specimens, dinosaur tracks, and fossils in settings and dioramas to fulfill any fascination with the history of Earth’s amazing creatures.

Philadelphia’s Academy of Natural Sciences unveiled the first fully mounted dinosaur in North America, Hadrosaurus foulkii, in 1868. Young dinosaur hunters will no doubt be impressed when confronted at the entrance by a forty-two-foot tall skeleton of the Giganotosaurus, at eight tons probably the largest predator ever to walk the earth. Among the thousands of collections of dinosaur and non-dinosaur species are more than thirty other dinosaur species, half of which are full skeletal mounts. Children can actually put on protective goggles and search for fossils in “The Big Dig,” an interactive area that is as entertaining as it is educational. There is much more to discover when visiting the venerable scientific institution, on the Benjamin Franklin Parkway.

A stop at The State Museum of Pennsylvania in Harrisburg offers exhibits exploring the history and diversity of life on earth in the Hall of Paleontology and Geology. Visitors can learn about fish from Pennsylvania’s seas dating to 367 million years ago, discover the secrets of the Carboniferous Forest of 310 million years ago, and witness technicians at work in the Dino Lab. The museum also exhibits outstanding objects and artifacts drawn from its vast collections relating to archaeology, ecology, the Civil War, industry, transportation, Pennsylvania’s founding, and the fine arts. The museum made worldwide news when its resident paleontologist, Dr. Robert M. Sullivan, participated in classifying and naming a new dinosaur species, Dracorex hogwartsia, that both honored and delighted Harry Potter author J. K. Rowling. A cast of the skull of this dinosaur will mesmerize visitors of all ages with its dragon-like appearance.

For Further Reading

Lea, Isaac. “On the fossil foot-marks in the Red Sandstones of Pottsville, Schuylkill County, Penna.” Transactions of the American Philosophical Society. Volume 10 (New Series), 1853.

One Hundred and Fifty Years of Publishing, 1785–1935. Philadelphia: Lea and Febiger, 1935.

Rogers, Henry Darwin. Geology of Pennsylvania: A Government Survey, With a General View of the Geology of the United States, Essays on Coal-Formation and its Fossils, and a Description of the Coal-Fields of North America and Great Britain. 2 Vols. Philadelphia: J. B. Lippincott, 1858.

Rudwick, Martin J. S. The Meaning of Fossils. Chicago: University of Chicago Press, 1976.

Scudder, Newton Pratt. The Published Writings of Isaac Lea, LL.D. Washington, D. C.: Bulletin of the United States National Museum, No. 23, 1885.

Wallace, Anthony F. C. St. Clair: A Nineteenth-Century Coal Town’s Experience with a Disaster-Prone Industry. New York: Alfred A. Knopf, 1987.

Spencer G. Lucas is curator of geology and paleontology at the New Mexico Museum of Natural History and Science in Albuquerque.

David L. Fillmore, while a student at Kutztown University of Pennsylvania in 2006, prepared a report on the Herbein Collection of the Reading Public Museum, which includes specimens found at Mount Carbon.

Edward L. Simpson is professor of geology and chair of the physical sciences department at Kutztown University of Pennsylvania.

Robert M. Sullivan is senior curator of paleontology and geology at The State Museum of Pennsylvania in Harrisburg.