Fossil Facts > Death of an Ichthyosaur 2
First picture is a well preserved ichthyosaur vertebra and neural arch. This specimen is a bit younger than those at Lyme, it comes from the middle Jurassic. It is rare to find an uncrushed and complete neural arch that is not in hard rock.
Picture 2 is a row of articulated ichthyosaur vertebrae, The centrums are almost perfectly aligned, one against the other. You are looking straight down on the centruma, where the spinal chord would have sat. The neurals have all fallen off, but are also still articulated. They were probably still held together by strong tendons , so fell as an articulated line.
Picture 2a shows a line of three articulated vertebra that have moved slightly more. The centra are now slipped and lean against each other. Ribs are on both sides of the vertebra but have been swept back against the vertebra (possibly by water currents). Should have had this fossil the other way up really, the neurals are at the bottom of the image.
The last two images show a beautiful uncrushed ichthyosaur centrum (Ophthalmosaur from the Oxford Clay). This one comes from towards the front of the animals body. You can see the big wide groove along the top that held the spinal chord. The two circular bumps on the side of the centrum are the attachments for the ribs. If you remember from earlier I said ichthyosaurs had double headed ribs on their body but single headed on the tail (more of that later!). The second image shows centrum that was lying on its side, probably as part of aa articulated row. The weight of sediment has crushed it into an oval shape.
Last picture is an extra that I added while writing this. I keep mentioning ichthyosaurs have a double headed rib. Here is a nice example.