Statisticians of Metropolitan Life Insurance Co. last week assembled and published the following facts concerning the viability of twins:
¶About one confinement in every hundred produces twins. The U. S. currently contains almost 4,000,000 twins600,000 male pairs, 625,000 female pairs, 635,000 mixed pairs. For some reason which biologists are trying to fathom mixed twins predominate at birth.
¶ A pair of male twins may expect to live jointly until the age of 46, mixed twins until the age of 48, female twins until the age of 50. Average duration of life for singly born men is...