watershedplus:

In 2004 researchers at Blue Reef Aquarium in Newquay commissioned glass sculptures, based on an original design dating back to the 1930s, to study the hermit crabs internal workings without having to resort to damaging the crustacean’s outer shell.
Recently the University of Otago, New Zealand, reproduced the experiment working with their scientific glass blower.

From the Blue Reef aquarium
and the University of Otago Glass blowing unit