Bacopa monnieri (Waterhyssop, Brahmi, Thyme-leafed gratiola, Water hyssop) is a perennial, creeping herb whose habitat includes wetlands and muddy shores. The word Brahmi is also the name given to Centella asiatica, particularly in North India,and Kerala where it is also identified in Malayalam as muttil(മുത്തിള്) or Kodakan. It seems that this identification of brāhmī as C. asiatica has been in use for long in northern India, as Hēmādri's 'Commentary on Aṣṭāṅgahṛdayaṃ (Āyuṛvēdarasāyanaṃ) treats maṇḍūkapaṛṇī (C. asiatica) as a synonym of brahmi." Warrier, P. K.; Nambiar, V. P. K.; Ramankutty, C.; Ramankutty, R. Vasudevan Nair (1996). Indian Medicinal Plants: A Compendium of 500 Species. Orient Blackswan. p. 238. ISBN 978-81-250-0301-4. http://books.google.com/?id=GkBRXzpqD98C&pg=PA238. although that may be a case of mistaken identification that was introduced during the 16th century.
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