English: This is the stinger of a queen wasp, Vespula vulgaris. It is contained in a vintage microscope slide set and dates to 1913. You can see the inner workings of a wasp's sting quite clearly at this resolution: two tiny barbs are contained in the tip. The first barb is thrust into the unfortunate receiver in order to stabilise the insect so it can deliver a second spike which injects the actual venom.
The shot was captured through a 19th century Broadhurst & Clarkson microscope, with my camera set up on a tripod looking directly down into the viewfinder. The photograph can be found in full resolution at this address.