"YE OTIS GHOSTE..."
See in text (Chapter III.)
Since Canterville Chase now belongs to the Otis family, the twins have changed Sir Simon's name from the Canterville ghost to the Otis ghost, expressing ownership over him and diminishing his influence by stealing his very name.
"the old withered almond-tree has blossomed..."
See in text (Chapter VI.)
The almond tree was mentioned in a part of the prophecy: "When the barren almond bears..." Sir Simon finally gets to experience a true death, and with his passing the near-dead almond tree awakens in full bloom. This symbolic expression of rebirth shows how the prophecy has been fulfilled and how peace can come to Canterville.