DINOFLAGELLATA 249 



G. cinctum E. (Fig. 106,/). Spherical to ovoid; annulus equatorial; 

 stigma horseshoe-shaped; 43/i by 40/i. 

 G. pulvisculum Stein (Fig. 106, g). No stigma; 38/x by 30/x. 

 G. uUginosum Schilling (Fig. 106, h). 36-48m by 30/x. 

 G. edax S. (Fig. 106, i). 34m by 33/x. 

 G. neglectum S. (Fig. 106, j)- 30-32/x by 29m. 



Family 2 Pronoctilucidae Lebour 



Genus Pronoctiluca Fabre-Domergue. Body with an antero- 

 ventral tentacle and sulcus; annulus poorly marked; salt water. 



P. tentaculatum (Kofoid and Swezy) (Fig. 107, a). About 54m long; 

 off California coast. 



Genus Oxyrrhis Dujardin. Subovoidal, asymmetrical posteriorly; 

 annulus incomplete; salt water. 



0. marina D. (Fig. 107, b). 10-37m long. 



Family 3 Pouchetiidae Kofoid and Swezy 



Ocellus consists of lens and melanosome (pigment mass); sulcus 

 and annulus somewhat twisted; pusules usually present; cytoplasm 

 colored; salt water (pelagic). 



Genus Pouchetia Schiitt. Nucleus anterior to ocellus; ocellus with 

 red or black pigment mass with a red, brown, yellow, or colorless 

 central core; lens hyaline; body surface usually smooth; ho lo zoic; 

 encystment common; salt water. Many species. 



P.fusus S. (Fig. 107, c). About 94m by 41m; ocellus 27m long. 



P. maxima Kofoid and Swezy (Fig. 107, d). 145m by 92m; ocellus 

 20m; off California coast. 



Genus Protopsis Kofoid and Swezy. Annulus and sulcus similar 

 to those of Gymnodinium or Gyrodinium; with a simple or compound 

 ocellus; no tentacles; body not twisted; salt water. A few species. 



P. ochrea (Wright) (Fig. 107, e). 55m by 45m; ocellus 22m long; 

 Nova Scotia. 



Genus Nematodinium Kofoid and Swezy. With nematocysts; 

 girdle more than 1 turn; ocellus distributed or concentrated, pos- 

 terior; ho lo zoic; salt water. 



A'', partitum K. and S. (Fig. 107,/). 91m long; off California coast. 



Genus Proterythropsis Kofoid and Swezy. Annulus median; ocel- 

 lus posterior; a stout rudimentary tentacle; salt water. One species, 



P. crassicaudata K. and S. (Fig. 107, g). 70m long; off California. 



Genus Erythropsis Hertwig. Epicone flattened, less than 1/4 

 hypocone; ocellus very large, composed of one or several hyaline 

 lenses attached to or imbedded in a red, brownish or black pigment 



