The majority of Trenton Group fossils residing in the Museum of Comparative Zoology (MCZ), and more importantly those specimens that are pictured throughout this webpage, come from a locality known as the Walcott-Rust Quarry. These specimens have come to light through the past work of Charles Doolittle Walcott (1850-1927), William Palmer Rust (1826-1897), and more recently Thomas E. Whiteley, at this little known site in central New York State.

Charles Doolittle Walcott, 1908

Image from Yochelson, 2001

The Walcott-Rust Quarry is situated along a creek, known as “Gray's Brook”, in Russia , New York . It was discovered in 1870 by 20-year-old Charles Doolittle Walcott, who was living with the Rust family. Walcott frequently visited the quarry with William Rust to excavate for fossils. Rust had been selling fossils from the area for some time and may have known of the site beforehand, but it was Walcott who brought the quarry to scientific recognition (Yochelson, in press). Rust would eventually purchase the area from the owner, Mr. Gray, with money he had received through the sale of fossils collected from the very land he was buying. The creek bordering the quarry passes through a steep abandoned railway embankment and winds its way through a small valley in the forest, ultimately feeding into the larger West Canada Creek further south. Today the area surrounding the quarry has changed since the years that Walcott and Rust toiled there. Much of the Rust Farm and neighboring area has been converted into a golf course and Trenton Gorge is now the site of a hydro-electric power plant. The flow of West Canada

Creek, which passes through the gorge, is presently controlled by four dams.

The Upper Ordovician limestone uncovered at the Walcott-Rust Quarry is a series of rocks most notably exposed in the Trenton Gorge. The Rust Formation is characterized by its highly bioturbated limestone (containing burrowing traces of infaunal organisms) and two distinct disturbed zones which show evidence for underwater channels and slumping of the sediment during deposition. The Walcott-Rust Quarry itself is outside of the gorge, almost a mile away. The same beds are also thought to be exposed further upstream at the northern tip of the gorge, near the village of Prospect . The limestone in these beds was deposited between the two disturbed zones so typical of the Rust Fm. and is an evenly layered, fine-grained limestone (lime mudstone). The creation of the quarry fossil beds is believed to be the result of turbidity currents (submarine landslides) or storm events (Brett et al. 1999). During these sudden events light sediment and suspended material were swept into deeper water and quickly deposited, thus creating an ideal environment for the preservation of any creatures that happened to be buried. Walcott and Rust noticed this throughout their digging along the edges of “Gray's Brook”, having found trilobites and other fossilized organisms in unusually great abundance. In recent years Brett et al. (1999) declared the quarry as “the single richest and most varied source of trilobites in the New York Trenton Group limestones and perhaps in the entire suite of New York Paleozoic rocks.”

The excellent preservation of trilobites at the quarry, particularly specimens of Ceraurus pleurexanthemus Green and Flexicalymene senaria Conrad, were of great importance to Walcott in his early research. A single thin bed, known as the Ceraurus layer, is recognized for being abundant in complete specimens of these two species. Partial or full enrollment of an individual trilobite is observed in many of these specimens and upon breaking them Walcott could see what looked like appendages. He spent much time preparing thin sections, grinding the limestone-entombed trilobites thin enough for light to pass through (see insert at left). As a result of his subsequent research and thin-sectioning of these specimens, Walcott is accepted as being among the first to identify trilobite appendages, including gills, legs, and other soft parts not commonly preserved. Many of these fossils he examined can still be found in the collections of the MCZ.

Nearly 60 years after C.D. Walcott's death, collecting at his quarry was resumed by Thomas E. Whiteley of Rochester, N.Y. Whiteley had been working for the Eastman Kodak Company when he became a devoted fossil collector. After retirement his boundless enthusiasm for collecting fossils compelled him to study regional paleontology. In the late 1970's and early 1980's Whiteley learned of the quarry while examining Walcott's specimens at Harvard. Realizing the importance of such a valuable asset to the scientific community, he decided to work and study the quarry himself.

Thomas E. Whiteley, 2004

In the early 1990's Thomas Whiteley almost single handedly re-excavated the Walcott-Rust Quarry. Information about the quarry's exact location had always been known to local citizens, and school field trips reportedly visited the site in the past. Even so, the scientific community had largely forgotten about the site, and it remained undisturbed since C.D. Walcott and William Rust had worked there. Whiteley discussed the location of the quarry with locals, who were happy to share their knowledge, and eventually tracked down the current owner of the property, William White. White directed him to a spot in the midst of a heavily wooded forest and down a railway embankment, where evidence of the old quarry was discovered. Whiteley noticed piles of broken and weathered slabs of limestone buried under leaves beside a small stream. The debris, he realized, was what remained of waste piles made by Walcott and Rust while they sorted through the limestone looking for fossils. A pit covered with vegetation cut into the steep slope of the valley is believed to be the original quarry. Once the quarry was found, a fresh exposure was opened and enlarged over a period of years with the help of a small crew and their bulldozers and backhoes.

Whiteley proceeded to study and document his finds in the limestone beds. He and family members carried and broke tons of rock, distinguishing 35 layers in a little less than two-meter vertical section from the floor to the top of the quarry. Whiteley labeled piles of these layers, left them to weather, then cut and polished cross-sections. The cut surfaces were etched with dilute hydrochloric acid, and the fossils within were recorded meticulously as to orientation, alignment, and position within beds. Whiteley re-examined some of Walcott's findings and obtained more detailed data on numbers of specimens with dorsal surface down, for example. He also documented species diversity for each layer.

Maps showing the location of the Walcott-Rust Quarry: (Top) Location of detail map. (Bottom) Detail map showing the quarry (marked with an arrow) and the Trenton Gorge. (Modified from Rudkin and Tripp, 1989)

Carlton E. Brett, Tom Whiteley, Peter A. Allison, and Ellis L. Yochelson studied the data amassed by Whiteley in order to document the sedimentology and taphonomy of the trilobite beds. They were able to interpret the paleoenvironmental setting and the geological events which resulted in this rare and unique preservation. One interesting factor that became obvious was that all the strata and the fauna throughout the quarry appear to be inverted. Their results were released in the Journal of Paleontology in 1999 under Brett et al.

The vast collection of fossils from the Walcott-Rust Quarry present in the MCZ was acquired from both C. D. Walcott and Thomas E. Whiteley. In the early 1870's Walcott began seeking a buyer for his fossils he had gathered over the few years he worked at the quarry. Originally James Hall of the New York State Museum was to obtain them, but due to financial troubles, he had to turn Walcott down. Louis Agassiz, the founder of the Museum of Comparative Zoology at Harvard, expressed an interest in purchasing the collection as he had heard from Hall that it was the finest collection known from the Trenton Group. In 1873 Agassiz purchased the it from Walcott for $3500. This collection consists of 325 trilobites, 190 crinoids, 6 starfish, 15 or so cystoids, as well as corals and brachiopods. Not only is this a collection of very well preserved specimens, but the locality data for each specimen is known and many of the specimens were painstakingly prepared and identified by Walcott (Yochelson, 1998). Walcott added to this collection more fossils he collected between 1873 and 1879 (Brett et. al., 1999). Walcott's thin sections that he used in describing trilobite appendages are also in the collections of the MCZ. Beginning in 1993 and continuing through early 2004, Thomas Whiteley has donated to the museum many of his specimens collected at the quarry. There are scores of trilobites, echinoderms, and other fossils from the quarry, a good number already prepared. The combined specimens of C.D. Walcott, Thomas Whiteley and others collected from the immediate area surrounding the quarry, number in the thousands.