The Peridiniaceae have been included among Flagellata under the title of Dinoflagellata.
Dinoflagellata, so called FIG.
The affinities of the Dinoflagellata are certainly with those Cryptomonadine Flagellates which possess two unequal flagella; the zoospores or young of the Cystoflagellates are practically colourless Dinoflagellates.