MASTIGOPHORA 29 



1. MONOSIGA Kent. Small colorless forms, solitary and sessile, 

 attached directly or by a short stalk : 9 species ; in fresh and salt water. 



M. ovata Kent (Fig. 28). Individual ovate or spherical; length .08 

 mm.: in fresh and salt water. 



2. CODONOSIGA Clark. Similar to Monosiga, but at the end of a 

 stalk and solitary or colonial: 1 species. 



C. botrytis Clark. From 1 to 20 individuals in a colony; length of 

 individual .08 mm., of stalk .014 mm. : in fresh and salt water. 



3. CODONOCLADIUM Stein. Like Codonosiga, but the stalk branches, 

 each branch bearing an individual: 4 species; in fresh and salt water. 



C. umbellatum Stein. Number of branches 4 to 10, which some- 

 times also branch ; length .03 mm. : in fresh water. 



4. SALPINGECA Clark. Solitary; body enclosed in a shell, usually 

 cup-shaped, which is directly attached at base or at the end of a short 

 stalk: about 27 species; in fresh and salt water. 



5. steini Kent. Shell cylindrical; length .02 mm.: in fresh water. 



ORDER 4. HETEROMASTIGIDA. 



Two or more flagella present, one of which is directed forwards and 

 the others backwards, during locomotion; no shell present; animal 

 colorless: 2 families. 



FAMILY BODONIDAE. 



Small, naked forms with 2 flagella of nearly equal length : 4 genera. 

 Key to the genera of Bodonidae here described: 



0! Flagella spring from anterior end. 



Z>! Flagella longer than body, which is ovate 1. BODO 



6 2 Flagella shorter than body, which is elongate 2. PHYLLOMITUS 



o 2 Flagella spring from a lateral groove 3. OXYBBHIS 



Fig. 29 Fig. 30 Fig. 31 



Fig. 29 Bodo caudatus (Calkins). Fig. 30 Phyllomitus amylophagus (Conn). 

 Fig. 31 Oxyrrhis marina (Calkins). 



1. BODO Ehrenberg. Body more or less ovate, often amoaboid; 

 anterior end pointed, with 2 flagella arising from a slight depression : 10 

 species; in salt and fresh water. 



B. caudatus (Dujardin) (Fig. 29). Body ovate, often amoeboid; 

 flagella about the same length; length .018 mm. 



