Off with its - ?nose? and some dental work as well.

The skull preparation is coming down to the final lap. I decided to take off the nose and repair a large crack that evidently occurred when the skull was buried. I can tell this because the material in the crack is the same as the surrounding matrix. Cracks that occurred after the sand has become rock are filled with plain calcite.

To do this repair, I dug down deep through the crack (which was 2 - 4 mm wide) with a narrow bit from the #5 Paleotool (c) until the nose broke off the rest of the skull. I then cleaned up all the excess matrix from the surfaces of the break and fit it back together. This resulted in a very clean fit of the parts in the original configuration. In addition, it gives us a chance to see the cross-section of the jaw bone structure. This is really cool since we won't be able to cut across the bone and section it after it is officially classified as a new animal (known as the Holotype).

So here are pictures: The skull before repair, with a tennis ball standing in for the eyeball

Here is the skull with the pieces all cleaned up and fit back together. The fit of the parts is very clean. They are not glued back together yet as it's easier to do the final preparation on smaller pieces. So I'm just holding them together by hand in this picture. The curve of the jaw is a little more pronounced after it's in the original location.

A closeup of the break, partially excavated with the Paleotool

The inside (center line view) of the nose after removal

A closeup of the center line view of the main skull end after nose removal

The end-on view of the broken cross-section of the skull end. I'll have to do something else to get a proper depth-of-field view of the break.

And here is the broken end of the jaw fragment

Here's a little better view of the complicated bone structure immediately under the teeth. (Top left corner of the bone fragment)

Here's the inside of the nose after final cleaning. Note that there is a small tapered groove running from the tip of the nose back to the nasal passages and the naris (nostril holes) at the rear of this fragment. I believe this passage is used for expulsion of salt-laden water produced by specialized glands. These glands are found in marine iguanas and sea birds, and this physiological adaption allows them to live full time in the ocean and drink salt water. I bet this has never been seen before in such an old animal!

Here are the teeth after cleaning. You can see the broken-off roots of many more teeth, and some holes where teeth would have been. I don't know if these were broken before or after death. There was a large bone (coricoid) laying across the jaw where the teeth were broken and touching it. That could have helped break off the teeth, though there are no serious scratches on the coricoid. Perhaps it just nestled in the available space as the bones were packed together. I count t least 8 broken or missing teeth. The missing teeth  will give us a good chance to study the tooth root structure later

Here is the main jaw. These were some serious teeth - over 6 mm in diameter. Tennis ball in the orbit.

And here's the entire jaw looking down into the teeth row.

I only have about 4-5 hours left and the skull will be finished. Then I will build the archival cradle to hold it.
Sincerely, Greg Carr