Magnificent Molluscs
This Blog was written as an expression about my interest in Geology, specifically on Taxonomy and Taphonomy of living things. As a result, Claire gave me a book about Mollusc Fossils called “The Atlas of Fossil Conchology” (location: F2.5, 564) and here is what I have to say about it. This book is a highly detailed and accurate overview of the depiction and appearance of many animals from the main fossil groups: Ammonoids, Bivalves, Belemnites and Brachiopods.
Ammonite (top left), Brachiopod (top right), Bivalve (bottom left) and Belemnite (bottom right – I need to study this group of fossils more).
The sketches of the fossils are also really detailed down to the most minute patterns, for example, the suture lines of an Ammonoid and also the distinction of the patterns of the suture lines by species (such as Goniatites having a simpler shape of Suture lines and the Ammonites having a pattern so complex that it is often times not detectable).
If we look closely, we can see the suture lines of this ammonite appearing shattered and complex. If we look closely into the goniatite, we can see that the suture line patterns are straightforward to understand – simpler and round in comparison.
The book also displays the distinction (though not compared) between the Bivalves and the Brachiopods rather than it being the same – such as the Brachiopod being more symmetrical on the shell (if we look at its front) than the Bivalves (as though not mentioned) and also the Bivalves having more muscle scars than the Brachiopods, and the Brachiopods also have pedicle outlets (to extrude it’s leg to stand out into the ocean floor) compared to a Bivalve which only has a pair of beaks.
The umbo of this bivalve is a beak rather than a hole so unlike the brachiopod there is no outlet for a pedicle. The Bivalves also have less muscle scars than the Brachiopods.
Another good thing about the book is that it has a vast range of fossils and species, and it also points out what makes the species special and unique while it was discovered, for example, some Bivalves having freckles all over the shell, some ammonoids having crests and some ammonoids being so perfectly formed that the aperture (cross section of the shell if we look at it from the front and back) is almost polygonal, and also having a lot of other shell shapes (Conchs and sea snails). There were even some ammonoids that were uncoiled which made them look more like a headless snake (Which was probably why, as a colleague of mine had pointed out, the Normans had believed that the ammonoids were beheaded snakes that had also coiled up) and also some that were shaped like the horn of a ram. Additionally, some of the pigments were also preserved but that was not confirmed as the illustrations were not colourised (published in the 19th century so colour printers were not really invented well yet).
Going back to this page, we can see a sea snail fossil that had been fractured.
Not only does this ammonoid’s (or rather Baculite’s) shell form in a typical manner, it also has sharp spikes protruding out of the shell. The other ammonoid/baculite is coiled up but not in the typical way an ammonite’s shell would form so it appears like a ram’s horn.
This book was also good at stating the anatomical features of the fossils (The Bivalves and Brachiopod distinction again, this time through the difference via the muscle scars with the Bivalves also having more muscle scars than the Brachiopods) and referring to them with particular scientific vocabulary – such as Discoidal and Aperture etc. This adds to the fact that the book (of which was published in 1889) is still published by a scientist despite palaeontology being established relatively lately at 1825. Then the annotations and numbering of the fossils were also really clear despite the numbering being really tiny, worn away and, in comparison to the shell, almost unnoticeable.
Overall, I felt myself using the minimum of skills that I would normally use when I am describing fossils and which groups they would normally belong to. I would recommend this book to students who are looking into the field of Taphonomy in the next few years and I can also recommend the book for those who enjoy describing and taking notes of fossil types and even retired Palaeontologists who are looking to sharpen their skills in identifying basic fossils again.
By Orelo Giovanni Verity (Prior Pursglove College student, Guisborough)
Reference:
Brown, C.T (1889). An Atlas Of The Fossil Conchology of Great Britain and Ireland with description of all the species. London, Swan Sonnenschein & Co, Paternoster square.
If you are interested in accessing this book please contact [email protected] or call in to see us, we are open Tuesday- Friday 10am- 4.30pm.
