Answer: Tibouchina urvilleana is the correct name for the Glory Bush. There are about 350 subspecies of Tibouchina, and semi-decandra describes the variety 'Princess Flower'. Other varieties fall under the heading of 'Alba' (meaning white), 'Multiflora' (many flowers), and 'Grandiflora' (large flower), etc. So, Tibouchina urvilleana is the Glory Bush. If yours is a named variety, it should have an additional name. Hope this clears things up!
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