Although used as a taxonomic category in some pre-Darwinian classifications, e.g., Linnaeus (1753), de Jussieu (1789), Horaninow (1843), Agassiz (1859), Wilson & Cassin (1864), in further classifications, the "algae" are seen as an artificial, polyphyletic group.
ɔːlðˈoʊ jˈuːzd æz ɐ tˌæksənˈɑːmɪk kˈæɾɪɡɚɹi ɪn sˌʌm pɹˈiːdɑːɹwˈɪniən klˌæsɪfɪkˈeɪʃənz, ˈiː.dʒˈiː., lˈɪniːəs wˈʌn θˈaʊzənd sˈɛvənhˈʌndɹɪd fˈɪfti θɹˈiː, də dʒˈʌsɪˌuː wˈʌn θˈaʊzənd sˈɛvənhˈʌndɹɪd ˈeɪɾi nˈaɪn, hˈoːɹɐnˌɪnoʊ wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd fˈoːɹɾi θɹˈiː, ˈæɡɐsˌɪz wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd fˈɪfti nˈaɪn, wˈɪlsən ænd kˈæsɪn wˈʌn θˈaʊzənd ˈeɪthˈʌndɹɪd sˈɪksti fˈoːɹ, ɪn fˈɜːðɚ klˌæsɪfɪkˈeɪʃənz, ðə "ˈælɡiː" ɑːɹ sˈiːn æz ɐn ˌɑːɹɾɪfˈɪʃəl, pˌɑːlɪfaɪlˈɛɾɪk ɡɹˈuːp.