Chapter 42 

 Order 3 Chonotricha Wallengren 



THESE ciliates live attached to aquatic animals, especially crus- 

 taceans and have developed a peculiar organization. The body is, 

 as a rule, vase-form with an apical peristome, around which extends 

 a more or less complicated ectoplasmic collar or funnel and along 

 which are found ciliary rows that lead to the deeply located cyto- 

 stome and cytopharynx. The macronucleus is oval and situated cen- 

 trally; there is a contractile vacuole usually near the cytopharynx. 

 Asexual reproduction is by lateral budding, and conjugation has been 

 observed in a few species. 



Family Spirochonidae Stein 

 Genus Spirochona Stein. Peristome funnel spirally wound; ciliary 

 zone on floor of the spiral furrow; attached to Gammarus in fresh 



Fig. 320. a, Spirochona gemmipara, X300 (Hertwig); b, Stylochona 

 coronata, X400 (Kent); c, Kentrochona nebaliae, X970 (Rompel); d, 

 Heliochona scheuteni, X550 (Wallengren); e, H. sessilis, X510 (Wallen- 

 gren); f, Chilodochona quennerstedti, X400 (Wallengren). 



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