Amman has one of twelve months' duration; Enguin, one of twelve months'; Buchner, a case of twelve months'; Benedictus, one of fourteen months'; de Blegny, one of nineteen months'; Marteau, Osiander, and others of forty-two and forty-four weeks'; and Stark's Archives, one of forty-five weeks', living, and also another case of forty-four weeks'.

An incredible case is recorded of an infant which lived after a three years' gestation.
Instances of twelve months' duration are also recorded.

Jonston quotes Paschal in relating an instance of birth after pregnancy of twenty-three months; Aventium, one after two years; and Mercurialis, a birth after a four years' gestation--which is, of course, beyond belief.
Thormeau writes from Tours, 1580, of a case of gestation prolonged to the twenty-third month, and Santorini, at Venice, in 1721, describes a similar case, the child reaching adult life.

Elvert records a case of late pregnancy, and Henschel one of forty-six weeks, but the fetus was dead.

Schneider cites an instance of three hundred and eight days' duration.