SPIROTRICHA, OLIGOTRICHA 



815 



Genus Tontonia Faure-Fremiet. With well-developed apical col- 

 lar; a long cytoplasmic (contractile) caudal process; salt water. 



T. gracillima F.-F. (Fig. 347, e). 48-52/z long; caudal process 

 250-300ju long; macronucleus moniliform; with zoochlorellae. 



Fig. 347. a, Halteria grandinella, X490 (Kahl); b, H. g. var. cirrifera, 

 X370 (Kahl); c, H. g. var. chlorelligera, X260 (Kahl); d, Strombidium 

 calkinsi, X900 (Calkins); e, Tontonia gracillima, X540 (Faure-Fremiet); 

 f, Strobilidium gyrans, X340 (Kahl); g, Tintinnidium fluviatile, X140 

 (Kent); h, i, T. semiciliatwn, X140 (Sterki); j, Strombidinopsis gyrans, 

 X270 (Kent); k, Tintinnopsis cylindrata, X440 (Daday); 1, T. illinoisen- 

 sis, X420 (Hempel); m, Codonella cratera, X540 (Faur6-Fremiet). 



Family 2 Strobilidiidae Kahl 



Genus Strobilidium Schewiakoff. Pyriform or turnip-shaped; cyto- 

 stome at anterior end; without cytopharynx; horseshoe-shaped 



