My daughter's Strathcona house, where we were housesitting last week, is a heritage home, dating from just before the turn of the 20th century. It's been renovated, some twenty years ago, but still retains its warped plank floors, intriguing angles, and vintage bathroom fixtures. And it's had one hundred and some years to collect silverfish.
glue, wallpaper paste, bookbindings, paper, photographs, starch in clothing, cotton, linen, rayon fabrics, wheat flour, cereals, dried meats, leather and even dead insects. (Pest Control Canada)
I found a helpful photo, with anatomical labels. The centre "tail" is simply called the "medial caudal filament": the "centre tail hair", in ordinary English. The two side ones are cerci, organs all insects have, but which are usually much smaller. They may be used as sensory organs. The female silverfish detects the male's sperm capsule with them, during the mating ritual. (Wikipedia) The short appendage in the centre is the ovipositor; this is a female.