Symbolic vs Constructive Delivery in the Law of Gifts

Someone asked me how these are different and I replied that are essentially the same in the sense that both are substitutes for actual delivery in cases involving situations in which actual, manual delivery is impractical.

But here is how one Commentator describes the distinction:

A delivery is symbolic when instead of the thing itself, some other object is handed over in its name and stead. A delivery is constructive, when in place of actual manual transfer the donor delivers to the donee the means of obtaining possession and control of the subject matter, or in some other manner relinquishes to the donee power and dominion over it.

Symbolic delivery occurred in In re Cohn, when Leopold delievered the birthday letter to his wife, Sara.

Constructive delivery occurred in Scherer v. Hyland, when the donor left the endorsed check in the apartment she shared with the donee.