Ciliophora 353 



left surface has occurred in Homalozoon. The Spathidiidae are typically 

 foraging carnivores which commonly prey on ciliates and flagellates. 



The family contains the following genera: Cranotheridium Schewiakoff (99), Diceras 

 Eberhard (99; Fig. 7. 10, H), Enchelydium Kahl (99; Fig. 7. 11, A), Homalozoon Stokes 

 (99), Legendrea Faure-Fremiet (99, 165; Fig. 7. II, D), Paraspatbidium Noland (158), 

 Penardiella Kahl (99; Fig. 7. II, B, C), Perispira Stein (48, 99; Fig. 7. 10, A-D). Spathi- 

 dioides Biodsky (99; Fig. 7. 10, F, G), Spathidiurn Dnjardin (99, 165, 226; Fig. 7. 10, 

 E), Teittopluys Chatton and Beauchamp (219; Fig. 7. 10, I, J). 



Family 75. Tracheliidae. The approximately circular cytostome, located 

 some distance from the anterior pole and at the end of a ventral row of 

 trichocysts, is surrounded by trichites or trichocysts and sometimes by 

 both (102). The body is completely ciliated. The Tracheliidae occur in 

 fresh and salt water and are typically carnivorous, feeding on other cili- 

 ates and on flagellates. 



Four genera have been assigned to the family: Branchioecetcs Kahl (102), Dileptus 

 Dujardin (102, 167, 215; Fig. 7. 11, F), Paradileptus Wenrich (220; Fig. 7. II, G), and 

 Trachelius Schrank (102. 165; Fig. 7. II, E). 



Suborder 2. TricJiostomina 



The cytostome usually lies at the base of a well-defined oral groove or 

 pit, the wall of Avhich bears one or more dense fields of adoral cilia. Such 

 fields often contain free cilia. However, both adoral membranelles and 

 an undulating membrane (or possibly a "pseudo-membrane") have been 

 reported in certain genera, such as Woodruffja (96) and Colpoda (211). 

 In some primitive Trichostomina, the cytostome lies almost at the an- 

 terior pole. More often, the mouth is shifted posteriorly on the ventral 

 surface. Spiral torsion of the body, tending to complicate peristomial 

 ciliary patterns, is characteristic of certain genera. Fifteen families have 

 been recognized. 



Family 1. Blepharocoridae. These ciliates occur in the digestive tract of 

 horses and ruminants. Somatic ciliation (Fig. 7. 12, A-C) is reduced to a 

 few anterior and posterior fields. One {Blepharocorys) or two {Charon) 

 groups of anal cilia lie near the posterior cytopyge, and there are two or 

 three distinct anterior groups. A band of slender adoral membranelles 

 has been reported in Blepharocorys (189). The antero-ventral cytostome 

 opens into a long ciliated pharynx. 



Two genera are referred to the family: Blepharocorys Bundle (91, 189; Fig. 7. 12, 

 A, B) and Charon Jameson (91, 93; Fig. 7. 12, C). 



Family 2. Clathrostomidae. The peristome is a shallow, uniformly cili- 

 ated ventral groove, with an oval cytostome lying in the anterior half. 

 The rim of the cytostome is a differentiated band from which circum- 

 pharyngeal fibrils extend into the endoplasm. 



