The Jurassic Williamsonia plant from Yorkshire as described and illustrated by Young & Bird in 1822

The earliest account of Yorkshire geology was provided by George Young and John Bird (the illustrator) in a large format 1822 book titled 'A Geological Survey of the Yorkshire Coast'. Their Plates II and III show images of fossil plants, with Plate II (see below) illustrating Middle Jurassic fern-like and cycad-like fossils, five of them from the 'Saltwick ironstone' near Whitby, and two from the 'coal shale' at Fryop (today Fryup on the North York Moors).

At first glance, the larger specimen (2) resembles the foliage of a modern cycad. Several others are similar to the foliage of modern ferns and one strange fossil (6) superficially resembles a flower. The authors commented that this last structure was 'apparently the head of the plant No. 2', a view that is still supported  today.








In the section on 'VEGETABLE REMAINS' in the book, the following account is given:

"Figures 2 and 6 of Plate II appear to belong to one plant ; the former being a leaf, somewhat imperfect, and the latter the head or fruit of the plant. The head is nearly entire, though depressed on the upper surface, and resembles that of the artichoke, cynara integrifolia, the covering, or calyx, consisting of numerous lanceolate and striated leaves, partly lying over one another, though not quite in the imbricated form. The correspondence of the leaves of the calyx, and some broken leaves adhering to the head, with the leaves or leafets in Fig. 2, appears to mark them out as belonging to one plant. Some imperfect stalks, in a decomposed state, which may have also appertained to this plant, have been found in the same place. In Fig. 6, may be seen the spot where the stalk has been attached to the head. The leaves of this singular plant often occur in the ironstone at Saltwick; but no other specimen of the head is known to have been found. The lanceolate leaves, or leafets, are often larger than those in Fig. 2; and generally present a convex surface, the middle of the leaf being raised. In correspondence with this, the underside of the leaves of the head are depressed in the middle."

Two specimens shown below, both found in the 20th century, match the examples described by Young and illustrated by Bird. They are from the same section of coast as those specimens and are shown below with their current names of Zamites gigas and Williamsonia gigas.


Zamites gigas foliage from the Aalenian Saltwick Formation, from a cliff fall near Whitby, North Yorkshire, 30 cm long, found 1988.



Williamsonia gigas, seed head or seed cone of the Williamsonia plant, diameter 65 mm, with individual bracts (there are 13 of them preserved at the surface of the specimen) reaching 45 mm in length. The central conical structure is about 22 mm in diameter.



While the Zamites foliage resembles that of extant cycads, the 'seed head' (sometimes described as a 'flower' despite the plant not being an angiosperm) is very different from the simple cones of cycads. Both belong to a plant named Williamsonia which is assigned to the extinct Bennettitales, a  group of plants ranging from Late Triassic to Late Cretaceous, superficially cycad-like, but with distinct reproductive structures.

It is fascinating to see that as of the time of writing the book, the specimen figured in Fig. 6, Plate II of Bird & Young (1822) was the only example known.

More specimens of Williamsonia can be seen in the Whitby Museum and the Yorkshire Museum in York (see below). 


Three Williamsonia seed heads in the Yorkshire Museum, York


Specimens in the Whitby Museum, Williamsonia at left, Weltrichia at right



Two renderings of the geological context of the finds are shown below, the first from Young & Bird (1822) and the second from Phillips (1829). My drone photograph shows the same area from a slightly closer and higher vantage point. 


Illustration of the Whitby coast in Young & Bird (1822). The grave of George Young (1777–1848) is in the churchyard of St Mary's at the top of the cliff, visible here in the illustration.


Note the annotation of 'Plants and Coal' at the left of this section in Phillips (1829).


My drone image of the same area. 









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