A bond given by an expectant, to become due on the death of a person from whom he will have property. A bond or agreement given by a borrower of money, by which he undertakes to pay a larger sum, exceeding the legal rate of inter- est, on or after the death of a person from whom he has expectations, in case of surviving him. Crawford v. Russell, C2 Barb. (N. Y.) 92; Boynton v. Ilubbard, 7 Mass. 119.