SPIROTRICHA, HETEROTRICHA 643 



10:1); macronucleus chain-form; peristome 2/3 the body length; 

 fresh water. 



*S. minus Roux (Fig. 303, b). 500-800/i long; macronucleus 

 chain-form; in fresh and salt water (Kahl). 



S. loxodes Stokes (Fig. 303, c). About 300/i long (length: width, 

 6-7:1); peristome about 1/3 the body length; oblique striation; 

 longer cilia at ends; macronucleus chain-form; fresh water. 



S. intermedium Kahl (Fig. 303, d). Slender; 400-600m long; macro- 

 nucleus chain-form; fresh water. 



*S. teres Claparede and Lachmann (Fig. 303, e). 150-400/x long; 

 macronucleus oval; in fresh water and also reported from salt water. 



S. filum (E.) (Fig. 303, /). Peristome 1/4 the body length; poster- 

 ior end drawn out; 200-300)u up to 700^ long; fresh water. 



Genus Gruberia Kahl. Similar to Spirostomum in general appear- 

 ance; but posterior end drawn out; slightly contractile; contractile 

 vacuole posterior; macronucleus compact or beaded; salt water. 



G. calkinsi Beltran (Fig. 303, g). 200-800^ long; peristome 2/3 

 the body length; many (contractile?) vacuoles distributed; Woods 

 Hole. 



Genus Blepharisma Perty. Pyriform, spindle-form or ellipsoid; 

 somewhat narrowed anteriorly; compressed; peristome on the left 

 border, which is twisted to right at posterior end and connected 

 with oral funnel with membrane; in front of cytostome a 2-layered 

 undulating membrane on right edge; ciliary rows longitudinal; cilia- 

 tion dense; contractile vacuole and cytopyge terminal; macronu- 

 cleus one or divided into several parts; several species rose-colored; 

 fresh or salt water. Many species. 



B. lateritium (Ehrenberg) (Fig. 302, g). 130-200m long; pyriform; 

 macronucleus oval; a micronucleus; rose-colored; fresh water among 

 decaying leaves. 



B. yersicinum P. (Fig. 302, h). 80-120^ long; elongate oval; 

 posterior end pointed; left peristomal edge sigmoid; preoral mem- 

 brane large; macronucleus in 3-7 parts; rose-colored; fresh water 

 among decaying vegetation. 



B. stcini Kahl (Fig. 302, i). 80-200/^ long; macronucleus ovoid; 

 reddish to colorless; fresh water in sphagnum. 



B. undulans Stein. 150-300/x long; macronucleus in 2 parts; un- 

 dulating membrane long; cyto pharynx directed posteriorly; fresh 

 water among decaying vegetation. Moore (1934) studied its con- 

 tractile vacuole and Giese (1938) observed the influence of light upon 

 its coloration (p. 38). Since gigantism has been noticed by Penard 

 it has been studied by several observers. Giese (1938) found that the 



