The Burgess shale occupies a unique location in paleontological history, and has played a significant role in both posing and answering questions for evolutionary biologists. It represents a small snapshot of life on the edge of a coastal shelf in Cambrian seas. Its discovery by Charles Walcott in the early 1900s was significant in that it was one of the first sites to yield up a large number of difficult-to-preserve soft-bodied organisms from a period when life was making the transition from simple to complex multicellular organisms. It has been referred to as a period of "biological experimentation", as evolution tossed up a number of innovative body plans, not all of which were adopted. Many of the critters uncovered are... weird... for lack of a better description. They are difficult to place within context of modern taxonomic groupings, as they are either "failed experiments" that went extinct, or their ancestors are so derived that it is almost impossible to detect the familial relationships.
Of course, many of the hypotheses set forth by the original site have now been supported or expanded by additional finds in the Chengjiang formation in China - and elsewhere around the world, but the wonder of remains are still being excavated from the original Global Heritage site that inspired so much thought.
These two creatures have wandered quite a distance from home to live in the muséum national d’Histoire naturelle:

This is Burgessia, a small and early crustacean from the eponymous shale. They probably lived a life similar to brine shrimp or krill, swimming and filter-feeding in the open ocean.

This is Naraoia, an early soft trilobite. I sometimes wish that these had not gone extinct, as I would like to try eating them. On the other hand, few folks eat horseshoe crabs, so...
It is sad to note the extensive water damage on both of the cards labeling these important fossils. All of these valuable fossils were stored in simple and poorly lit plexiglass cases, and not all of them were labeled. There were no educational or supplemental materials to really place the organisms in their evolutionary or historical context. They were simply objects to be appreciated for their natural beauty, and it was sad to see such an amazing resource callously gathering dust in an empty display case. Even my own personal collection of odds and ends from the natural world is better organized and placed in a more meaningful context.
Maybe I'll open my own museum some day.