https://en.wikipedia.org/wiki/Rock_ptarmigan

let me try and remember...was each of those metro stations...linked to a hunted species of bird?

https://uk.news.yahoo.com/photos/incredible-pictures-moscow-metro-stations-132800209/majestic-colourful-stations-taganskaya-very-photo-132800276.html

TAGANSKAYA...that was it...the prague Rothschild was to think about punning around taganskaya and ptarmigan to create a memory aid...but then gave up...

and that member of Norwegian intelligence (in the CID) used to project 'ptarmigan' now and then...in touch/direct contact with the Romanov cat?