The gowns were for the rector and pro-rector (some would say the vice chancellor and the pro vice chancellor) of Karolinska Institutet , Sweden's oldest medical universtiy. They are celebrating their 200-year jubilee this year, and wanted new gowns for the highest officials. (So now you know why the snakes are there... :-)
The gowns were first worn at the ceremony of promotion of the new doctors (I guess I should say the ceremony of conferment of the PhD degree in medicine) last week.
Now I have found the site for all the photos of the event. There are a lot, so... here is a short list of the photos most interesting to me:
This shows the rector in front, the pro rector in the background (opens in new window). Click "next" for a picture of the pro rector.
I also like this photo. Photo nr 499 and 501 are nice, too.