Either before going out to Malabar as bishop, or during a later visit to the west, Jordanus probably wrote his Mirabilia, which from internal evidence can only be fixed within the period 1329-1338; in this work he furnished the best account of Indian regions, products, climate, manners, customs, fauna and flori given by any European in the Middle Ages - superior even to Marco Polo's. In his triple division of the Indies, India Major comprises the shorelands from Malabar to Cochin China; while India Minor stretches from Sind (or perhaps from Baluchistan) to Malabar; and India Tertia (evidently dominated by African conceptions in his mind) includes a vast undefined coast-region west of Baluchistan, reaching into the neighborhood of, but not including, Ethiopia and Prester John's domain. Jordanus' Mirabilia contains the earliest clear African identification of Prester John, and what is perhaps the first notice of the Black Sea under that name; it refers to the author's residence in India Major and especially at Kollam, as well as to his travels in Armenia, north-west Persia, the Lake Van region, and Chaldaea; and it supplies excellent descriptions of Parsee doctrines and burial customs, of Hindu ox-worship, idol-ritual, and suttee, and of Indian fruits, birds, animals and insects. After the 8th of April 1330 we have no more knowledge of Bishop Jordanus I.
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