The monastic institutions, particularly those of Egypt, about the year 400, are described by four curious and devout travellers - Rufinus (Vit. Patrum, 1. ii. iii. p. 424-536), Posthumian (Sulp. Sever. Dialog. i.), Palladius (Hist. Lausiac. in Vit. Patrum, p. 709-863 [783]), and Cassian (see in tom. vii. Bibliothec. Max. Patrum, his four first books of Institutes, and the twenty-four Collations or Conferences).