There were three Venetian painters named Bellini. Jacopo (c. 1400-1470/1) was the father. Gentile Bellini (c. 1429-1507) is said to be his elder son, and Giovanni Bellini (c. 1431-1516) his younger son. Ruskin presumably has in mind here the two brothers, as there is no evidence of his being familiar with the work of Jacopo.