As the adventures of Proba and her family are connected with the life of St. Augustin, they are diligently illustrated by Tillemont, Mem. Eccles. tom. xiii. p. 620-635. Some time after their arrival in Africa, Demetrias took the veil and made a vow of virginity; an event which was considered as of the highest importance to Rome and to the world. All the 'Saints' wrote congratulatory letters to her; that of Jerom is still extant (tom. i. p. 62-73, ad Demetriad. de servanda Virginitat. [Epist. cxxx. tom. i. p. 969, ed. Vallars.]), and contains a mixture of absurd reasoning, spirited declamation, and curious facts, some of which relate to the siege and sack of Rome.