In a recent series of related papers [1,2], we called attention to the use of simple statistical distribution functions in the treatment of molecular size distributions of polymers. The basic distribution functions involved are the binomial, the Poisson, and the negative binomial distributions with discrete, nonzero variables. Depending on the physical conditions imposed, these distributions can be combined in a variety of ways to yield more complicated size distributions. Such combinations are exemplified by the convolution of distributions in addition polymers, the power series distribution for simple condensation polymers, the Lagrange distribution for branched polymers, etc. The most complicated case is a compound Lagrange distribution for the condensation of polymer chains with a primary size distribution [2].