240 THE ESSEX NATURALIST.
NOTE ON BICOECA PLANKTONICA Kisseljev.
There seems no doubt that the organism recorded and figured
(Fig. 4) in this paper under the name of Bicoeca plank tonka is the
same as that described under that name by Kisseljev (1931).
Organisms with identical or very similar cases have, however,
been described on several occasions under different names, e.g.,
Codonomonas Pascheri Van Goor (1925) and W. Conrad (1938),
Pseudokephyrion conicum J. Schiller (1929) and Codomonas
annulata J. B. Lackey (1939). But whether the actual organisms
contained in these cases were all of the same type appears
doubtful. As described and figured by Kisseljev, and confirmed
by my own observations, the organism appeared to be a typical
Bicoeca. On the other hand Van Goor and Lackey regarded it
as a member of the Oicomonadaceae. Schiller, however, described
it as biflagellate with golden yellow chromatophores and regarded
it as a Chrysomonad. Conrad also regarded it as a Chrysomonad
as he found characteristic cysts within the case, although the
organism seen by him was colourless. Bicoeca planktonica has
been previously recorded as British by J. W. G. Lund (1942).
EXPLANATION OF FIGURES.
1. Spermatozopsis exultant Korschikoff.
2. Amphidinium ? larvale Lindemann.
3. Chrysococcus rufescens Klebs.
4. Bicoeca planktomca Kisseljev.
5. Chlorella sp.
6. Scourfieldia complanata West.
7. Zoospore of a Chytrid.
8. Chroomonas nordstedtii Hansgirg.
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