JOHANNA, HINZUAN, or ANZUAN, one of the Comoro islands, situate in the Mozambique Channel, between Africa and Madagascar. It is of an irregular triangular form, 24 miles in length by 18 in breadth, and is highly picturesque. Its highest peak, in S. Lat. 12. 15., E. Long. 44. 29., rises about 6000 feet above the sea-level. The soil is fertile and well watered, producing cocoa-nuts, limes, oranges, yams, rice, millet, &c. Pop. about 20,000.