222 PROTOZOOLOGY 



P. ochrea (Wright) (Fig. 101, e). 55/x by 45)u; ocellus 22/i long; 

 Nova Scotia. 



Genus Nematodinium Kofoid et Swezy. With nematocysts; 

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

 terior; holozoic; salt water. 



N. partitum K. et S. (Fig. 101,/). Ol^i long; off CaHfornia. 



Genus Proterythropsis Kofoid et Swezy. Annulus median; ocel- 

 lus posterior; a stout rudimentary tentacle or prod-like antapical 

 process; salt water. One species. 



P. crassicaudata K. et S. (Fig. 101, g). 70/u 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 pig- 

 ment body with a red, brown or yellow core, located at left of 

 sulcus; sulcus expands posteriorly into ventro-posterior tentacle; 

 salt water. Several species. 



E. cornuta (Schlitt) (Fig. 101, h). 104^ long; off California (Ko- 

 foid and Swezy). 



Family 4 Noctilucidae Kent 



Tentacle somewhat contractile, arises from sulcal area and ex- 

 tends posteriorly; this group had formerly been included in the 

 Cystoflagellata; studies by recent investigators, particularly by 

 Kofoid, show their affinities with the present suborder; holozoic; 

 salt water. 



Genus Noctiluca Suriray. Spherical, bilaterally symmetrical; 

 peristome marks median line of body; a cytostome at bottom of 

 peristome; with a conspicuous tentacle; cytoplasm much vacuo- 

 lated, and cytoplasmic strands connect central mass with periph- 

 ery; peripheral granules phosphorescent (p. 95); cytoplasm 

 colorless or blue-green; sometimes tinged with yellow coloration 

 in center; swarmers formed by budding, and each possesses one 

 flagellum, annulus, and tentacle; widely distributed in salt water; 

 holozoic. One species. 



N. scintillans (Macartney) {N. miliaris S.) (Fig. 101, i, j). 

 Usually 500-1000;u in diameter, with extremes of 200/i and 2 mm. 

 Gross (1934) observed that complete fusion of two swarmers 

 (isogametes) results in cyst formation from which trophozoites 

 develop. Acid contents of the body fluid is said to be about pH 3. 



Genus Pavillardia Kofoid et Swezy. Annulus and sulcus similar 

 to those of Gymnodinium; longitudinal flagellum absent; stout 



