This is the strict technical expression used to describe the ownership in “an estate in fee-simple in possession in a corporeal hereditament.” The word “seised” is used to express the “seisin” or owner’s possession of a freehold property: the phrase “in de mesne,” or “in his demesne,” ( in dominico suo) signifies that he is seised as owner of the land itself, add not merely of the seigniory or services; and the concluding words, “as of fee,” import that he is seised of an estate of inheritance In fee-simple. Where SEISI 101 the subject is incorporeal , or the estate expectant on a precedent freehold, the words “in his demesne” are omitted. (Co. Litt. 17a; Fleta, 1. 5, c. 5,