INFUSORIA 



67 



8. Operctjlaria Ehrenberg. Like Pyxidium, but colonial; whole 

 colony rigid: 8 species; in fresh water. 



0. articulata Ehr. Body spindle- 

 shaped, truncate at lower end, and .05 mm. 

 long: on water beetles. 



9. CoTHURNiA Ehren- 

 berg. Body elongate and 

 enclosed in a colorless or 

 brownish cup, at the bot- 

 tom of which it is at- 

 tached and into which it 

 can retract; cup also at- 

 tached either directly or 

 by a short stalk: numer- 

 ous species; in fresh and 

 salt water. 



C. crystallina Ehr. (Fig. 124). Length of cup .07 to .2 mm.: in 

 fresh and salt water; Woods Hole. 



Fig. 123- 



-Epistylis flavicans 

 (Conn). 



Fig. 124 



Cuthuniin crys- 

 tallina 

 (Calkins). 



Subclass 2. SUCTORIA. 



Usually sessile Infusoria which have no cilia as adults but are pro- 

 vided with long hollow tentacles adapted for sucking or piercing; they 

 attach the tentacles to other Infusoria and suck them out; some are 

 entoparasites in Infusoria: 8 families with about 200 species. 



Key to the families of Suctoria here described : 



«! Body globular, without a cup 1. Podophryidae 



«2 Body not globular. 



\ Body usually in a cup at end of a slender stalk 2. Acinetidae 



62 Body without cup or stalk ; tentacles knobbed 3. Dendrosomidae 



Family 1. PODOPHEYIDAE. 



Body globular and not in a cup; stalked or ..^ 



not, and with tentacles of different kinds, some 

 knobbed and some acute: 5 genera. -..^ 



1. Sph-EROPHRYA Claparede and Lachmann. 



Body spherical or ovoid and without stalk, with -t-^—r^ 



knobbed tentacles radiating from all sides : free- ^ ' '■' " 



living in swamps and infusions or entoparasites Fig. 125 — Sphcero- 



. . phrija magna 



in Stentor, Paramecium, and other cihates; 4 (Conn). 



species. 



S. magna Maupas (Fig. 125). Diameter .06 mm.: among water 



plants. 



