Clean, gut, and wash 12–16 navaga. Salt the fish, sprinkle with a little ground pepper, and wipe with a napkin. Cut each fish into thirds, dip into flour, fry in 2–3 spoons of some kind of fast day oil, and cool. Prepare an aspic from 2 lbs small fish and 2 zolotniki fish glue. Clarify the aspic with caviar by pounding the caviar and boiling it together with the aspic. Strain through a napkin tied to the legs of a stool. Pour a little aspic into a mold and cool it. Add lemon slices, greens, and 15–20 boiled and shelled crayfish tails, top with pieces of navaga, and cover with aspic. Cool and turn out onto a platter.