To determine which horses are ponies, we need to check their heights and see if they are less than 14.2 hands (which is equivalent to 58.8 inches, since 14.2 hands x 4 inches/hand = 58.8 inches).
Please provide the heights of the horses: Darla, Wilma, Beacon, Lily, and Nellie, so we can identify which ones qualify as ponies.