Peel cucumbers, remove seeds and grate.
Add vinegar and sprinkle with salt and white pepper.
Let stand for 20 minutes.
Drain off liquid, reserving 3 tablespoons.
Soften gelatin in reserved liquid, then dissolve in hot chicken bouillon.
Combine with grated cucumber, and add green food coloring to make a pale green.
Pour into a sectioned ice cube tray, chill in refrigerator and, when firm, remove divider.
Serve in separate plates over lettuce leaves; dot with allowed mayonnaise (one tablespoon per serving).
Add a rolled strip of pimento for color, if desired.