Folklore of fossil fish

Fish are the most diverse animals with backbones – that is, vertebrates – living today. Bone and teeth of fishes abound in the fossil record, from the armour-plated, primitive fishes of the Devonian, through the cartilaginous sharks with their shiny dagger-like teeth, to the bones of advanced ray-finned teleosts related to modern carp and cod.
Along with other marine fossils, fossil fishes were once used as ‘proof’ of the biblical deluge, for example, the fabulous Cretaceous fossil fish deposits of Lebanon. Gayet et al. (2012) recorded that, in the third century, the Bishop of Palestine wrote:

Fig. 1. A so-called ‘petrified nail’, about 150mm long, as depicted by Hugh Miller. These fossils represent the central process of the median dorsal plate of the placoderm fish, Homosteus milleri.

“That Noah’s Flood covered the highest mountains is for me the truth, and I say that the witness of my eyes confirms it: for I have seen certain fishes, which were found in my lifetime on the highest peaks in Lebanon. They took stones from there for construction, and discovered many kinds of sea fishes which were held together in the quarry with mud, and as if pickled in brine were preserved until our times, so that the mere sight of them should testify to the truth of Noah’s Flood”.

Fig. 2. Median dorsal plate of Homosteus figured by Hugh Miller. The central process was referred to in Caithness and Orkney folklore as a ‘petrified nail’.

Petrified nails

Hugh Miller, in his book Foot-prints of the Creator (Miller, 1849), mentioned that amateur geologists of Caithness and Orkney would refer to one particular fossil in the Old Red Sandstone, presumably relatively common, as ‘petrified nails’ (Fig. 1). These are, in fact, the central processes of the median dorsal plate of the large placoderm fish, Homosteus milleri. Note that Miller erroneously referred to them as a part of the hyoid plate of another fish, Asterolepis (Fig. 2). It is not known whether the name ‘petrified nail’ was a simple allusion to the nail-like shape of the fossil or signified a belief that they were ancient nails entombed in rock.


Toadstones are the button-shaped fossil teeth of the Jurassic–Cretaceous fish, Lepidotes (Figs. 3 and 4). In folklore, they were once thought to have come from the heads of living toads. Toads were of particular interest to medical practitioners during the seventeenth century (Baldwin, 1993), when it was believed that concoctions made from pulverised toads could provide protection against bubonic plague if placed in an amulet and worn around the neck or wrists. This was justified on several grounds, notably that the toad’s warty skin resembled the carbuncles and spots developed by plague victims.

Fig. 3. ‘Toadstones’ varying in size from 3mm to 13mm. Top row: Lepidotes sp. tooth crowns from Wicklesham Quarry, Faringdon, Oxfordshire (Early Cretaceous Faringdon Sponge Gravels, but the vertebrate fossils found here are deriv ed from the Late Jurassic Kimmeridge Clay). Middle row: Lepidotes sp. and pycnodont tooth crowns from Ardley, near Bicester, Oxfordshire (Bathonian, from the clay layer immediately above the White Limestone containing the famous dinosaur footprints). Bottom row: Lepidotes sp. tooth crowns from Veizeys Quarry, Tetbury, Gloucestershire (Bathonian Athelstan Oolite Formation, Forest Marble Member) (all MS collection).

Much has been written about toadstones. They are mentioned in literature as far back as the Roman scholar, Pliny the Elder, who died in the famous AD 79 eruption of Mount Vesuvius that destroyed Pompeii. In fact, it has been suggested that the legends about toadstones originated with the name ‘Batrachites’ (frogstone) given to them by Pliny (Lankester, 1920). Lankester stated that they were so-named because their drab colour resembled that of a toad. Subsequently, the vivid imaginations of medieval physicians may have been responsible for myths about the origin and mystical powers of toadstones.

Fig. 4. ‘Toadstones’ from the collection of Walter Mantell now housed in the NHMUK. These examples of Lepidotes teeth came from the Lower Cretaceous (Wealden) of Tilgate Forest, Sussex.

The naturalist, Robert Brookes (1763, p. 162), described the colour and shape of toadstones, remarking that:
“… some suppose it to be the tooth of a fish; but this does not seem to agree with its shape”.

Toadstones were even alluded to by William Shakespeare in As You Like It, Duke Senior saying in Act 2, Scene 1:
“Sweet the uses of adversity. Which, like the toad, ugly and venomous, Wears yet a precious jewel in his head”.

But how could toadstones be obtained? Topsell (1608) gave instructions on the extraction of the stone from the toad, which had to be alive at the time for the stone to retain its powers. The toad should be placed on a red cloth to act as a distraction and, while it ‘played’, the stone would fall from its head. Lupton (1627) suggested an equally imaginative way of extracting toadstones, which involved putting the toad into an earthen pot on an ant hill and covering it with earth. The ants would eventually eat the toad, leaving its bones and the toadstone in the pot to be collected.

Toadstones were once widely employed in jewellery. Several toadstones formed part of the famous Cheapside Hoard, a mass of Elizabethan and Jacobean jewellery discovered in 1912 by workmen in the City of London. Their use was not only for aesthetic reasons, but also because they were believed to counteract poison and be efficacious against epilepsy. It was thought that a toadstone set in an open ring would give off heat to the finger on which it was worn when poison was detected (Kunz, 1917). Kennedy (1976) suggested that toadstones were believed to change colour if a poison was present. The use of toadstones against all kinds of poisons was mentioned by Lupton (1627), who noted that:

“A Tode stone (called Crapaudina) touching any part be venomed, hurte or stung with Ratte, Spider, Waspe or any other venomous Beasts, ceases the paine or swelling thereof”.
The early literature also records medicinal uses for toadstones as cures for sores, fever, bowel problems and labour pains (Fig. 5).

‘True’ toadstones comprising Lepidotes teeth were sometimes substituted in Scotland by brown-coloured pebbles, which, like Lepidotes teeth, were often set in rings.
What kind of fish was Lepidotes? Sometimes written Lepidotus, Lepidotes was a primitive bony fish related to modern gars. Inhabiting both freshwater lakes and shallow seas, species of Lepidotes could grow to over two metres in length (Fig. 6). The body was covered with thick, enamel scales. Batteries of peg-like teeth (Fig. 7) – the toadstones – enabled Lepidotes to crush the shells of its molluscan prey. Interestingly, the remains of Lepidotes have been discovered alongside those of the Early Cretaceous dinosaur, Baryonyx, suggesting that it, in turn, was preyed on by this fish-eating giant.

Serpents’ eyes

Fossil palatal teeth of another bony fish – the white sea bream Sargus – were known as serpents’ eyes in Maltese fossil folklore (Fig. 8). Sharing a similar crushing function to the teeth of Lepidotes, serpents’ eyes have a strong resemblance to toadstones. They may have a pale yellow or orange-coloured centre called the acrodin cap, surrounded by a darker brown ring, giving them an eye-like appearance. Along with tongue stones (sharks’ teeth; see below), serpents’ eyes were given as gifts in Malta during medieval times (Zammit-Maempel, 1989). For instance, papal delegates to Malta were presented with gold-mounted serpents’ eyes and tongue stones to be used as protective amulets. Their importance and value extended to British royalty: serpents’ eyes were listed among the jewels owned by King Henry V of England (Thompson, 1932).

Fig. 5. Woodcut illustration from Hortus Santatis (1491) by Johannes de Cuba (1430– 1503), showing the extraction of a ‘toadstone’ from a gigantic amphibian for use on a sick patient with a bloated abdomen.

The idea that Sargus teeth from the Miocene of Malta were the petrified eyes of serpents is connected with the story of the shipwrecking of St Paul described below. As the supposed petrified eyes of serpents, they were employed as a sympathetic medicine (‘like cures like’) against snakebites, either by boiling the fossil teeth in water or adding them in powdered form to water or wine.

Swallow Stones and Fairy Saltcellars

Pycnodonts are an extinct order of bony fish. Their teeth were one of the sources of Lapis chelonius or Swallow Stones used in medieval medicines (Duffin, 2015).
Fossil vertebrae of bony fishes (‘ichthyospondyli’) were reported by Edward Lhuyd (1660–1709) to have been called Fairy Saltcellars by some rustic people (Duffin and Davidson, 2011).

Fig. 6. A drawing of the Jurassic–Cretaceous bony fish Lepidotes, the peg-like teeth of which were known as toadstones in folklore.

Tongue stones

Sharks have cartilaginous skeletons, but their teeth consist of resistant calcium phosphate (Fig. 9). Consequently, the fossil record of sharks largely comprises teeth, which can be found in great variety and abundance all over the world, especially in Mesozoic and Cenozoic rocks. Given that an individual great white shark has more than 300 teeth in its jaws at any one time, and that teeth are shed regularly during the life of the shark, it is hardly surprising that sharks’ teeth can be very abundant fossils.

Fig. 7. A tooth plate of Lepidotes mantelli from the Lower Cretaceous (Wealden) of Sussex, showing the peg-like crushing teeth (‘toadstones’) in situ.

Fossil sharks’ teeth were popularly known as tongue stones – Glossopetrae (Latin) – in folklore before their origin became more widely understood. In Europe, tongue stones were also known by various other names, including Linguae Melitenis (Maltese tongues), Linguae S. Pauli or Ilsien San Pawl (tongues of St Paul; see Zammit-Maempel, 1975), Lingui di Serpi, and in Germany Natternzungen (adders’ tongues) or Schlangenzungen (serpents’ tongues). There was also a belief in the fifteenth and sixteenth centuries that they were the tongues of witches with a taste for the blood of young children (see Duffin and Davidson, 2011).

Tongue stones were often considered in ancient times to have ‘grown’ naturally within the rock. This process, called vis-plastica, was once a popular explanation for the origin of fossils in general. It was thought that tongue stones could spontaneously generate themselves, as some fossils had smaller lateral projections (Fig. 10), which were considered to be offspring still attached to their parents.

Fossil sharks’ teeth are especially associated with the small Mediterranean island of Malta, where they were once collected in great numbers. Indeed, during medieval times, Malta was the centre of a flourishing trade supplying fossil sharks’ teeth to many other European countries. A popular Maltese legend concerns St Paul the Apostle, who was shipwrecked on the island in AD 60 along with his fellow sailors. As written in the Acts of the Apostles, St Paul was bitten by a snake, which rose out of a fire built to warm the shipwrecked sailors. St Paul flung the snake back into the fire. The heathen islanders noted that he was unharmed, convincing them that he was a god. As a punishment to the snakes of the island, he reputedly took away their ability to produce poison (Zammit-Maempel, 1989). The cursed Maltese snakes also lost their eyes and tongues. Different fossils found in the Miocene rocks of Malta are believed to be serpents’ eyes (as described above) and serpents’ tongues (sharks’ teeth).

Fig. 8. Display panel from the National Museum of Natural History in Mdina, Malta, showing: (top) the jaw of a modern Sargus (white sea bream) containing peg-like crushing teeth; (left) a ‘serpent’s eye’ tooth from a Miocene relative: (right) and a similar fossil tooth (right), which may be incorrectly labelled as Lepidotus (=Lepidotes).

As a result of their connection with St Paul, all tongue stones from Malta were considered to possess supernatural powers, especially against poison. The use of tongue stones for medical purposes was once widespread in Malta. Indeed, in 1768, they are listed among the medicines available from the pharmacy of Santo Spirito Hospital in Rabat, Malta. Their most common medicinal use was as a cure for, or a safeguard against, poison (Zammit-Maempel, 1989). This use persisted until at least 1940: Zammit-Maempel (1990) told how members of the Maltese community living in North Africa asked their relatives to send them tongue stones to be hung on the backs of their doors for protection against vipers and scorpions. Tongue stones could be mounted as pendants worn as necklaces or bracelets for their anti-poison powers. Others were mounted in base or precious metals and attached to silver or gold watch chains (Zammit-Maempel, 1989). Tongue stones were also formerly placed by the bedsides of Maltese women to help during childbirth (Zammit-Maempel, 1989).

Zammit-Maempel (1966) recounted the story of a mother who came to a doctor’s surgery in Malta. Seeing a shark’s tooth on the doctor’s desk, she told him that her young son had been slow in talking and only uttered his first words at the age of four after she had held a tongue stone against his tongue, closed his mouth and prayed to St Paul.
During the fifteenth century in Malta, tongue stones were suspended from the branches of Mediterranean corals to form so-called languiers. Languiers and other ornately mounted tongue stones were placed on side tables (Kredenzen) during banquets. Guests would select a tongue stone from the languier, immerse it in their wine and could rest assured that they would not succumb to poisoning.

An entirely different legend about fossil sharks’ teeth developed in Japan. Here, teeth of the giant shark, Carcharocles megalodon, are in folklore thought to be the thumbnails of Tengu Man, a mythical mountain goblin with a long, Pinnochio-like nose.
A juvenile Carcharocles megalodon (Agassiz)) tooth, found by Mark Renz in a freshwater stream in DeSoto County, Florida and featured in his book Megalodon: Hunting the Hunter (Renz, 2002), has a hole drilled through the root and some obvious modifications to the original shape of the tooth (Fig. 11). This modified tooth can be compared with a similar tooth from South Carolina (Fig. 12). Renz speculated that the serrations had been sanded off and that scratch marks on the surface were the result of rubbing against clothing when a Native American wore the tooth as a pendant. Native Americans would have been well aware of megalodon teeth as they are relatively abundant in the coastal areas of Florida and North and South Carolina.

Fig. 9. ‘Tongue stone’, a tooth of the shark Oxyrhina from the Miocene of Malta. The resemblance with an animal tongue is clear in this example.

Tongue stones and solving the mystery of fossils

Tongue stones were very familiar to seventeenth century naturalists and played a pivotal role in the early history of palaeontology and the understanding of the true origin of fossils. They were among the first fossils examined in the context of having an organic origin and not simply as supernatural objects. Steno (1638–1686), originally called by his Danish name Niels Stensen, was a noted physician interested in the natural sciences. He worked in Florence under the patronage of the Medici family. In October 1666, a large shark was brought ashore by fishermen near Livorno in Tuscany. Grand Duke Ferdinand II ordered that it be taken to Florence for Steno to dissect. Steno’s examination of the shark’s head convinced him that tongue stones had to be the teeth of ancient sharks.

However, Steno realised that there were some differences between tongue stones and the teeth of contemporary sharks, surmising that tongue stones came from sharks that must no longer exist, thereby acknowledging the almost heretical notion of species extinction. Furthermore, because tongue stones are collected on land, he suggested that the sea must formerly have covered the land for the sharks to live there.

In 1667, Steno published a book describing his studies of the shark’s teeth and also proposing a theory for the formation of stratified rocks, which is close to what we now know to be correct. This work, entitled Elementorum Myologiae Specimen, seu, Musculidescripto Geometrica cui accedunt Canis Carchariae Dissectum Caput, et Dissectus Piscis ex Canum Genere, is a seminal volume for palaeontologists and geologists alike (Cutler, 2003).

Fig. 10. Tooth of the shark, Lamna obliqua, from the Eocene London Clay of Sheppey in Kent. The lateral denticles in such ‘tongue stones’ were believed by some to represent new teeth growing spontaneously in the rock.

Folklore and the early history of the science that became known as palaeontology are intertwined. Folkloric interpretations of fossils were often founded on similarities in appearance between fossils and living animals, and these interpretations were given serious consideration by naturalists engaged in the study of fossils. Although many folklore beliefs about fossils seem absurd in a modern context, they usually have a rational origin revealing how mysterious objects, such as fossils, were identified by comparison with items from everyday life, for example, masonry nails and animal’s tongues.

Fig. 11. Perforated Carcharocles megalodon tooth featured in Renz (2002), about 50mm long. Original rendition by Teri Risi.
Fig. 12. Carcharocles megalodon tooth from Broad River, Beaufort County in South Carolina. Scale bar = 1 cm (MS collection). Compare this with the modified tooth shown in Fig. 11.


Baldwin, M.R. 1993. Toads and plague: amulet therapy in seventeenth-century medicine. Bulletin of the History of Medicine 67: 227–247.
Brookes, R. 1763. A New and Accurate System of Natural History. Volume 5: The Natural History of Waters, Earths, Stones, Fossils and Minerals, with their Virtues, Properties, and Medicinal Uses, to which is added, the Method in which Linnaeus has treated these subjects. London: J. Newbery.
Cutler, A. 2003. The Seashell on the Mountain top. New York: Dutton.
Duffin, C. J. 2015 Historical survey of the internal use of unprocessed amber. Acta Medico-Historica Adriatica 13(1): 41–74.
Duffin, C. J. & Davidson, J. P. 2011. Geology and the dark side. Proceedings of the Geologists’ Association 122: 7–15.
Gayet, M., Abi Saad, P. & Gaudant, O. 2012. The Fossils of Lebanon. Memory of Time. Méolans-Revel: Éditions DésIris.
Kennedy, C. B. 1976. A fossil for what ails you. The remarkable history of fossil medicine. Fossil Magazine 1: 42–57.
Kunz, G. F. 1917. Rings for the Finger. From the earliest known times to the present, with full descriptions of the origin, early making, materials, the Archaeology, history, for affection, for love, for engagement, for wedding, commemorative, mourning, etc. Philadelphia & London: Lippincott.
Lankester, E. R. 1920. More Science from an Easy Chair. London: Methuen & Co.
Lupton, T. 1627. A thousand Notable things of sundrie sortes: Whereof some are wonderfull, some strange, some pleasant, divers necessary, a great sort profitable, and many very precious. London: Wright and Bird.
Miller, H. 1849. Footprints of the Creator: or, the Asterolepis of Stromness. London: Johnstone & Hunter.
Renz, M. 2002. Megalodon – Hunting the Hunter. Lehigh Acres: PaleoPress.
Thompson, C. J. S. 1932. A Mediaeval poison cup made from the Terra Sigillata. British Medical Journal 1: 73–74.
Topsell, E. 1608. The Historie of Serpents. London: Jaggard.
Zammit-Maempel, G. 1975. Fossil sharks’ teeth: a medieval safeguard against poisoning. Melita Historica 6: 391–406.
Zammit-Maempel, G. 1989. The Folklore of Maltese fossils. Papers in Mediterranean Social Studies 1: 1–29.
Zammit-Maempel, G. 1990. Rock from St. Paul’s Grotto (Malta) in Medicine and Folklore. Rabat: Progress Press.

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