248 PROTOZOOLOGY 



E. apora Schiller. Compressed, oval; striae on margin of valves; 

 chromatophores numerous yellow-brown, irregular in form; S0-32fx 

 by 21-26)u (Schiller); 17-22m by 14-19^ (Lebour; Martin); common 

 in brackish water, New Jersey. 



Suborder 2 Peridiniinea Poche 



Typical dinoflagellates with one to many transverse annuli and 



a sulcus; 2 flagella, one of which undergoes a typical undulating 



movement, while the other usually directed posteriorly. According 



to Kofoid and Swezy, this suborder is divided into two tribes. 



Body naked or covered by a thin shell Tribe 1 Gymnodinioidae 



Body covered by a thick shell Tribe 2 Peridinioidae (p. 257) 



Tribe 1 Gymnodinioidae Poche 

 Naked or covered by a single piece cellulose membrane with an- 

 nulus and sulcus, and 2 flagella; chromatophores abundant, yellow 

 or greenish platelets or bands; stigma sometimes present; asexual 

 reproduction, binary or multiple division; holophytic, holozoic, or 

 saprozoic; the majority are deep-sea forms; a few coastal or fresh 

 water forms also occur. 



With a cellulose membrane Family 1 Cystodiniidae 



Without shell 



Furrows rudimentary Family 2 Pronoctilucidae (p. 249) 



Annulus and sulcus distinct 

 Solitary 



With ocellus Family 3 Pouchetiidae (p. 249) 



Without ocellus 



With tentacles Family 4 Noctilucidae (p. 251) 



Without tentacles 



Free-living Family 5 Gymnodiniidae (p. 251) 



Parasitic Family 6 Blastodiniidae (p. 254) 



Permanently colonial Family 7 Polykrikidae (p. 257) 



Family 1 Cystodiniidae Kofoid and Swezy 

 Genus Cystodinium Klebs. In swimming phase, oval, with ex- 

 tremely delicate envelope; annulus somewhat acyclic; cyst-mem- 

 brane drawn out into 2 horns. 



C. steini K. (Fig. 106, d, e). Stigma beneath sulcus; chromato- 

 phores brown; swarmer about 45)u long; freshwater ponds. 



Genus Glenodinium Ehrenberg. (Glenodiniopsis, Stasziecella 

 Woloszynska). Spherical; ellipsoidal or reniform in end-view; an- 

 nulus a circle; several discoidal, yellow to brown chromatophores; 

 horseshoe- or rod-shaped stigma in some; often with gelatinous en- 

 velope; fresh water. Many species. 



