Sunday, February 1, 2015

Another Month, More Skull Parts

We have been focusing on bones that appear to be skull parts since they tell us so much about new animals, and are generally very descriptive and unique. We know from having three brain cases that we have parts of three skulls in this first block we are excavating. We now have as well three specimens of the left side of the skull roof that include the pineal gland. I believe these are found in the parietal and frontal bones.

Here is the latest bone - the anterior part (front part) is toward the left with the midline running along the top of the piece. This piece has a very delicate part left on the rear-projecting spur on the lower left in this picture. I believe it is the supratemporal and the squamosal. These are missing from the other two pieces.

Here are a couple of closeups of the posterior projection of the spur. The fin is only about 1 mm thick and (of course) it was difficult to prepare. 

This one shows the interior of the braincase and the pineal gland as well. 

Here is the one before that. I can't seem to find it totally prepared in this same position, so here it is with the anterior end (front end) pointing up. The pineal is the notch on the right side, the brain case in the lower projection on the right. 
 And here is the third one. It is the most broken piece, but the pineal and some of the midline suture rugosity is evident upon inspection.

When we get these all together we will compare sizes. It is my impression that the largest piece is actually from the largest skull, but it awaits accurate dimensioning. Two of these fragments are already in Alaska so I can't do it right now. I have begun scanning parts with two new students at Century High School. After all the skull bones that are here in Oregon are scanned they will be sent to the U of Alaska, Fairbanks, to join the rest of the skull parts. 

Sincerely, Greg Carr 

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