Another specimen from the Miskatonic University collection, this time from the 1927 expedition to the Congo. As usual, things didn't end well.
The glowing fluid is a by product of illuminating the interior of the jar with reflected light. The tabletop is lit by shop lights on both sides. Light passes into the jar and gets bounced off a circle of white paper sitting under the jar and a rectangle behind it. I stumbled across the idea trying to get decent shots of specimens floating in fluid.
If you like it, the specimen is currently on Ebay .