Some of the more common forms of benefit involving compound interest and mortality are merely variations of one general contract, and are in their limiting cases identical. For example, a short-term policy becomes simply a whole-life assurance when the term is indefinitely extended; and limited-payment policies and endowment assurances continually approach the whole-life contract as the number of payments or the term of the endowment is increased. When more than one life is involved the benefit, if payable on the first death, is of a slightly different nature, but if payable on the death of the last survivor—in the case of either a joint or a contingent assurance—it approaches in one of its limiting cases merely a whole-life policy on a single life. The object of the present paper is to consider in a general way some features of the curves of the values under different classes of policy, and to notice how these curves are affected by Select Mortality and other factors.