MASTIGOPHORA, CHRYSOMONADINA 201 



stage. Incomplete separation of the daughter individuals followed 

 by repeated fission, results in numerous colonial forms mentioned 

 elsewhere (p. 146). Some resemble higher algae very closely. Sexual 



(^^ 



Fig. 88. The life-cycle of Chromulina, X about 200 (Kiihn). a, encyst- 

 ment; b, fission; c, colony-formation; d, palmella-formation. 



reproduction is unknown in this group. Encystment occurs com- 

 monly ; in this the fiagellum is lost and the cyst is often enveloped by 

 a silicious wall possessing an opening with a plug. 



The chrysomonads inhabit both fresh and salt waters, often occur- 

 ring abundantly in plankton. 



Motile stage dominant Suborder 1 Euchrysomonadina 



Palmella stage dominant 



Sarcodina-like; flagellate stage unknown 



Suborder 2 Rhizochrysidina (p. 209) 



With flagellate phase Suborder 3 Chrysocapsina (p. 210) 



Suborder 1 Euchrysomonadina Pascher 



With or without simple shell 



One flagellum Family 1 Chromulinidae 



2 flagella 



Flagella equally long Family 2 Syncryptidae (p. 205) 



Flagella unequally long Family 3 Ochromonadidae (p. 206) 



With calcareous or silicious shell 



Bearing calcareous discs and rods. . . .Family 4 Coccolithidae (p. 208) 

 Bearing silicious skeleton. Family 5 Silicoflagellidae (p. 209) 



Family 1 Chromulinidae Engler 



Minute forms, naked or with sculptured shell; with a single flagel- 

 lum; often with rhizopodia; a few colonial; free-swimming or at- 

 tached. 



